Probe for nuclear magnetic resonance and its cooling circulation system

Abstract

The present application relates to the field of nuclear magnetic resonance technology, and aims to solve the problem of how to improve the utilization rate of refrigerant and reduce consumption, and provides a probe and cooling circulation system for nuclear magnetic resonance. The probe for nuclear magnetic resonance includes a signal detection component and a cooling component. The signal detection component is used to detect nuclear magnetic resonance signals. The cooling component includes a capillary evaporator, a working fluid circulation pipeline and a JT throttle. The capillary evaporator is fitted with the signal detection component to cool the signal detection component. One end of the working fluid circulation pipeline is connected to the inlet end of the capillary evaporator, and the other end is connected to the outlet end of the capillary evaporator. The JT throttle is arranged at a position of the working fluid circulation pipeline close to the inlet end of the capillary evaporator. The JT throttle is used to reduce the pressure of the working fluid at the inlet end of the capillary evaporator to further cool the working fluid, which is conducive to the working fluid quickly cooling the signal detection component, so as to achieve the effect of improving the utilization rate of the refrigerant and reducing consumption.

Description

Technical Field

[0001] The present application relates to the field of nuclear magnetic resonance technology, and in particular to a probe for nuclear magnetic resonance and a cooling circulation system thereof. Background Art

[0002] Magnetic resonance technology, as an efficient and nondestructive analytical method, is widely used in various analytical and detection fields. However, its relatively low sensitivity has long limited its development. As a key component for stimulating nuclear spin resonance and detecting NMR signals, lowering the probe temperature can effectively reduce thermal noise, improve the signal-to-noise ratio, and enhance signal detection sensitivity. Generally, the lower the probe temperature, the higher the detection sensitivity. Currently, ultra-low probe temperatures are primarily achieved using liquid nitrogen and liquid helium.

[0003] In existing technologies, ultra-low temperature cooling sources are primarily delivered to the cold end through pipelines, where heat conduction cools the probe. However, existing cooling pipelines suffer from low refrigerant utilization and high refrigerant consumption. Solving these technical problems is a concern for those skilled in the art. Summary of the Invention

[0004] The first aspect of the present application provides a probe for nuclear magnetic resonance, and the second aspect provides a cooling circulation system to solve the problem of how to improve the utilization rate of refrigerant and reduce consumption.

[0005] In a first aspect, an embodiment of the present application provides a probe for nuclear magnetic resonance (NMR) comprising a signal detection component and a cooling component. The signal detection component is used to detect NMR signals. The cooling component comprises a capillary evaporator, a working fluid circulation pipeline, and a JT throttle. The capillary evaporator is bonded to the signal detection component to cool the signal detection component. One end of the working fluid circulation pipeline is connected to the inlet end of the capillary evaporator, and the other end is connected to the outlet end of the capillary evaporator. The JT throttle is disposed on the working fluid circulation pipeline near the inlet end of the capillary evaporator. The JT throttle is used to reduce the pressure of the working fluid at the inlet end of the capillary evaporator to further cool the working fluid.

[0006] Compared with the prior art, the probe for nuclear magnetic resonance provided in this embodiment transports cooling working fluid to the capillary evaporator through a working fluid circulation pipeline. The capillary evaporator fits and is in full contact with the signal detection component, which is conducive to heat exchange between the working fluid and the signal detection component, thereby improving the utilization rate of the working fluid and reducing consumption. In addition, the probe for nuclear magnetic resonance reduces the pressure of the working fluid at the inlet end of the capillary evaporator through a JT throttle to further cool the working fluid, which is conducive to the working fluid quickly cooling the signal detection component, thereby achieving the effect of improving the utilization rate of the cooling working fluid and reducing consumption.

[0007] In a possible embodiment, the JT throttle includes a first connection part, a pressure reducing part, and a second connection part that are connected in sequence, the first connection part is connected to the working fluid circulation pipeline, the inner diameter of the pressure reducing part is smaller than the inner diameter of the first connection part, the working fluid in the working fluid circulation pipeline flows from the first connection part into the pressure reducing part to reduce the pressure and temperature of the working fluid, and the second connection part is used to output the refrigerant working fluid to the capillary evaporator.

[0008] The inner diameter of the pressure-reducing portion is smaller than the inner diameter of the first connecting portion, so that the high-pressure refrigerant encounters increased resistance when flowing through the pressure-reducing portion of the JT throttle, resulting in a pressure drop, thereby further reducing the temperature of the refrigerant. This is conducive to the refrigerant quickly cooling the signal detection component, thereby achieving the effect of improving the utilization rate of the refrigerant and reducing consumption.

[0009] In a possible embodiment, the pressure reducing part includes a first through hole and a second through hole, one end of the first through hole is connected to the first connecting part, and the other end is connected to the second through hole, the inner diameter of the first connecting part, the inner diameter of the first through hole and the inner diameter of the second through hole decrease successively, and the second through hole is connected to the second connecting part.

[0010] The inner diameters of the first connecting portion, the first through hole, and the second through hole decrease in sequence, so that the resistance of the high-pressure refrigerant increases when flowing through the JT throttle, resulting in a pressure drop, thereby further reducing the temperature of the refrigerant. This is conducive to the refrigerant quickly cooling the signal detection component, thereby achieving the effect of improving the utilization rate of the refrigerant and reducing consumption.

[0011] In a possible implementation, there are multiple second through holes, the multiple second through holes are arranged in parallel, and the first through hole is connected to the second connection through the multiple second through holes.

[0012] Before throttling, if the pressure of the working medium is too high, the probe for nuclear magnetic resonance is provided with a plurality of second through holes, thereby accelerating the rapid throttling and cooling of the working medium and improving the throttling and cooling rate.

[0013] In a possible embodiment, the probe for nuclear magnetic resonance further includes a first Tesla valve, one end of the first Tesla valve being connected to the second connection portion of the JT throttle and the other end being connected to the inlet end of the capillary evaporator, and the first Tesla valve being used to increase the flow rate of the refrigerant.

[0014] After the working fluid passes through the JT throttle to reduce pressure and cool down, its flow rate slows down. The probe used for nuclear magnetic resonance compensates for the slow flow rate of the working fluid through the JT throttle through the first Tesla valve. This is conducive to the smooth flow of the working fluid into the signal detection component for cooling, thereby achieving the effect of improving the utilization rate of the refrigerant and reducing consumption.

[0015] In a possible implementation, the probe for nuclear magnetic resonance further includes a second Tesla valve, and the second Tesla valve is provided at the outlet end of the capillary evaporator.

[0016] The second Tesla valve is located in the path where the working fluid returns to the circulation pump. The second Tesla valve can not only speed up the flow rate of the working fluid, but also reduce the blockage of the working fluid circulation pipeline caused by the backflow of the working fluid.

[0017] In a possible implementation, the capillary evaporator includes a plurality of bent portions, and the plurality of bent portions are used to increase a contact area with the signal detection component.

[0018] The shape of the bent portion can be U-shaped or S-shaped to lengthen the length of the capillary evaporator, thereby increasing the contact area between the capillary evaporator and the signal detection component, which is beneficial to heat exchange between the working fluid and the signal detection component, thereby improving the utilization rate of the working fluid and reducing consumption.

[0019] In a possible embodiment, the probe for nuclear magnetic resonance further includes a shell, the shell is hollow and has a accommodating chamber, the signal detection component and the capillary evaporator are arranged in the accommodating chamber, and the shell is detachably connected to the working medium circulation pipeline.

[0020] The accommodating chamber forms a vacuum environment by evacuating the air to reduce heat transfer and reduce the temperature rise of the signal detection component and the capillary evaporator, which is beneficial to improving the cooling efficiency of the working fluid, thereby improving the utilization rate of the working fluid and reducing consumption.

[0021] In a second aspect, an embodiment of the present application provides a cooling circulation system, comprising a working fluid circulation pump, a precooler, a cold head assembly, and a probe for nuclear magnetic resonance. The working fluid circulation pump is connected to the working fluid circulation pipeline, and the working fluid circulation pump is used to pressurize the working fluid. The precooler is connected to the output end of the working fluid circulation pump, and the precooler is used to precool the pressurized working fluid. The cold head assembly includes a helium compressor, a first-stage cold head, and a second-stage cold head. The helium compressor is connected to the first-stage cold head and the second-stage cold head respectively, and the helium compressor is used to cool the first-stage cold head and the second-stage cold head. The first-stage cold head and the second-stage cold head are spaced apart in the working fluid circulation pipeline to cool the precooled working fluid. The JT throttle is used to reduce the pressure of the cooled working fluid to further cool the working fluid.

[0022] Compared with the existing technology, the cooling circulation system provided in this embodiment pressurizes the working fluid in the working fluid circulation pipeline through the working fluid circulation pump, and the precooler and cold head assembly cool the working fluid in turn, and reduces the pressure of the working fluid at the inlet end of the capillary evaporator through the JT throttle to further cool the working fluid. This is conducive to the working fluid quickly cooling the signal detection component, so as to achieve the effect of improving the utilization rate of the refrigeration working fluid and reducing consumption.

[0023] In one possible embodiment, the cooling circulation system further includes a dewar tank, within which the precooler, the first-stage cold head, the second-stage cold head, and the JT throttle are disposed, and the working fluid circulation pump and the helium compressor are disposed externally. The nuclear magnetic resonance probe further includes a flange joint and a housing, the housing having a hollow interior and a housing chamber, the signal detection assembly and the capillary evaporator being disposed within the housing chamber, and the housing being detachably connected to the dewar tank via the flange joint.

[0024] The Dewar tank creates a vacuum environment by evacuating the air to reduce heat transfer and reduce the temperature rise of the precooler, first-stage cold head, second-stage cold head and JT throttle, which is beneficial to improve the cooling efficiency of the working fluid, thereby improving the utilization rate of the working fluid and reducing consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1 This is a schematic structural diagram of a cooling circulation system and a probe for nuclear magnetic resonance according to an embodiment of the present application;

[0027] Figure 2 for Figure 1 A schematic diagram of an embodiment of a JT throttle for a nuclear magnetic resonance probe;

[0028] Figure 3 for Figure 1 A schematic diagram of another embodiment of a JT throttle for a nuclear magnetic resonance probe;

[0029] Figure 4 for Figure 1 A schematic diagram of an embodiment of a capillary evaporator for a nuclear magnetic resonance probe;

[0030] Figure 5 for Figure 1 A schematic diagram of another embodiment of a capillary evaporator for a nuclear magnetic resonance probe.

[0031] Description of main component symbols:

[0032] 1. Probe for nuclear magnetic resonance imaging; 11. Signal detection assembly; 12. Cooling assembly; 121. Capillary evaporator; 1211. Bending portion; 1212. Outlet end; 1213. Inlet end; 122. Working fluid circulation pipeline; 123. JT throttle; 124. First connecting portion; 125. Pressure reducing portion; 126. Second connecting portion; 127. First through hole; 128. Second through hole; 13. First Tesla valve; 14. Second Tesla valve; 15. Housing; 16. Flange joint; 2. Cooling circulation system; 21. Working fluid circulation pump; 22. Precooler; 23. Helium compressor; 24. First-stage cold head; 25. Second-stage cold head; 26. Dewar tank; 27. Vacuum joint. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments.

[0034] Some embodiments of the present application are described in detail. In the absence of conflict, the following embodiments and features of the embodiments can be combined with each other.

[0035] Example

[0036] See also Figure 1 As shown, this embodiment provides a probe 1 for nuclear magnetic resonance (NMR) including a signal detection component 11 and a cooling component 12. The signal detection component 11 is used to detect NMR signals. The cooling component 12 includes a capillary evaporator 121, a working fluid circulation pipe 122, and a JT throttle 123. The capillary evaporator 121 is attached to the signal detection component 11 to cool the signal detection component 11. One end of the working fluid circulation pipe 122 is connected to the inlet end 1213 of the capillary evaporator 121, and the other end is connected to the outlet end 1212 of the capillary evaporator 121. The JT throttle 123 is arranged on the working fluid circulation pipe 122 near the inlet end 1213 of the capillary evaporator 121. The JT throttle 123 is used to reduce the pressure of the working fluid at the inlet end 1213 of the capillary evaporator 121 to further cool the working fluid.

[0037] The probe 1 for nuclear magnetic resonance provided in this embodiment transports cooling working fluid to the capillary evaporator 121 through the working fluid circulation pipe 122. The capillary evaporator 121 is in close contact with the signal detection component 11, which is conducive to heat exchange between the working fluid and the signal detection component 11, thereby improving the utilization rate of the working fluid and reducing consumption; and the probe 1 for nuclear magnetic resonance reduces the pressure of the working fluid at the inlet end 1213 of the capillary evaporator 121 through the JT throttle 123 to further cool the working fluid, which is conducive to the working fluid quickly cooling the signal detection component 11, thereby improving the utilization rate of the refrigeration working fluid and reducing consumption.

[0038] In this embodiment, the signal detection component 11 includes a probe coil and a low-noise amplifier circuit. The capillary evaporator 121 contacts the surfaces of the probe coil and the low-noise amplifier circuit respectively to cool the signal detection component 11, thereby improving the signal-to-noise ratio of the magnetic resonance signal.

[0039] Please combine Figure 2 and Figure 3 As shown, in a possible embodiment, the JT throttle 123 includes a first connection part 124, a pressure reduction part 125 and a second connection part 126 that are connected in sequence, the first connection part 124 is connected to the working fluid circulation pipeline 122, the inner diameter of the pressure reduction part 125 is smaller than the inner diameter of the first connection part 124, the working fluid in the working fluid circulation pipeline 122 flows from the first connection part 124 into the pressure reduction part 125 to reduce the pressure and temperature of the working fluid, and the second connection part 126 is used to output the refrigerant working fluid to the capillary evaporator 121.

[0040] In this embodiment, the inner diameter of the pressure reducing portion 125 is smaller than the inner diameter of the first connecting portion 124, so that the high-pressure refrigerant is subjected to increased resistance and a pressure drop when flowing through the pressure reducing portion 125 of the JT throttle 123, thereby further reducing the temperature of the refrigerant. This is conducive to the refrigerant quickly cooling the signal detection component 11, so as to achieve the effect of improving the utilization rate of the refrigerant and reducing consumption.

[0041] In the first possible implementation of the JT throttle 123, please combine Figure 2 As shown, the pressure reducing part 125 includes a first through hole 127 and a second through hole 128. One end of the first through hole 127 is connected to the first connecting part 124, and the other end is connected to the second through hole 128. The inner diameters of the first connecting part 124, the first through hole 127 and the second through hole 128 decrease successively, and the second through hole 128 is connected to the second connecting part 126.

[0042] In this embodiment, the inner diameters of the first connecting portion 124, the first through hole 127, and the second through hole 128 decrease successively. The resistance encountered by the high-pressure refrigerant when flowing through the JT throttle 123 increases, resulting in a pressure drop, thereby further reducing the temperature of the refrigerant. This is conducive to the refrigerant quickly cooling the signal detection component 11, thereby achieving the effect of improving the utilization rate of the refrigerant and reducing consumption.

[0043] In the second possible implementation of the JT throttle 123, please combine Figure 3 As shown, a plurality of second through holes 128 are provided, and the plurality of second through holes 128 are arranged in parallel, and the first through hole 127 is connected to the second connection through the plurality of second through holes 128 .

[0044] In this embodiment, if the pressure of the working fluid is too high, the probe 1 for nuclear magnetic resonance is provided with a plurality of second through holes 128 , thereby accelerating the rapid throttling and cooling of the working fluid and improving the throttling and cooling rate.

[0045] In a possible embodiment, the probe 1 for nuclear magnetic resonance further includes a first Tesla valve 13, one end of the first Tesla valve 13 is connected to the second connection portion 126 of the JT throttle 123, and the other end is connected to the inlet end 1213 of the capillary evaporator 121, and the first Tesla valve 13 is used to increase the flow rate of the refrigerant.

[0046] In this embodiment, the Tesla valve can be made by bending the transmission pipeline.

[0047] After the working fluid passes through the JT throttle 123 to reduce pressure and cool down, the flow rate of the working fluid slows down. The probe 1 for nuclear magnetic resonance compensates for the slow flow rate of the working fluid passing through the JT throttle 123 through the first Tesla valve 13, which is conducive to the smooth flow of the working fluid into the signal detection component 11 for cooling, thereby achieving the effect of improving the utilization rate of the refrigeration working fluid and reducing consumption.

[0048] In a possible implementation, the probe 1 for nuclear magnetic resonance further includes a second Tesla valve 14 , which is disposed at the outlet end 1212 of the capillary evaporator 121 .

[0049] In this embodiment, the second Tesla valve 14 is provided on the path where the working medium returns to the circulation pump. The second Tesla valve can not only speed up the flow rate of the working medium, but also reduce the blockage of the working medium circulation pipeline 122 caused by the backflow of the working medium.

[0050] Please combine Figure 4 and Figure 5 As shown, in a possible embodiment, the capillary evaporator 121 includes a plurality of bent portions 1211 , and the plurality of bent portions 1211 are used to increase the contact area with the signal detection component 11 .

[0051] In this embodiment, the shape of the bending portion 1211 can be U-shaped or S-shaped to lengthen the length of the capillary evaporator 121, so that the contact area between the capillary evaporator 121 and the signal detection component 11 is increased, which is beneficial to the heat exchange between the working fluid and the signal detection component 11, thereby improving the utilization rate of the working fluid and reducing consumption.

[0052] In a possible embodiment, the probe 1 for nuclear magnetic resonance further includes a shell 15 , which is hollow and has a receiving chamber. The signal detection component 11 and the capillary evaporator 121 are arranged in the receiving chamber. The shell 15 is detachably connected to the working medium circulation pipe 122 .

[0053] In this embodiment, the accommodating chamber forms a vacuum environment by evacuating the air to reduce heat transfer and reduce the temperature rise of the signal detection component 11 and the capillary evaporator 121, which is beneficial to improving the cooling efficiency of the working fluid, thereby improving the utilization rate of the working fluid and reducing consumption.

[0054] In a second aspect, an embodiment of the present application provides a cooling circulation system 2 comprising a working fluid circulation pump 21, a precooler 22, a cold head assembly, and a probe 1 for nuclear magnetic resonance. The working fluid circulation pump 21 is connected to the working fluid circulation pipeline 122, and is used to pressurize the working fluid. The precooler 22 is connected to the output end of the working fluid circulation pump 21, and is used to precool the pressurized working fluid. The cold head assembly includes a helium compressor 23, a first-stage cold head 24, and a second-stage cold head 25. The helium compressor 23 is connected to the first-stage cold head 24 and the second-stage cold head 25, respectively, and is used to cool the first-stage cold head 24 and the second-stage cold head 25. The first-stage cold head 24 and the second-stage cold head 25 are spaced apart from the working fluid circulation pipeline 122 to cool the precooled working fluid. The JT throttle 123 is used to reduce the pressure of the cooled working fluid to further cool the working fluid.

[0055] The cooling circulation system 2 provided in this embodiment pressurizes the working fluid in the working fluid circulation pipe 122 through the working fluid circulation pump 21, and the precooler 22 and the cold head assembly cool the working fluid in turn, and reduces the pressure of the working fluid at the inlet end 1213 of the capillary evaporator 121 through the JT throttle 123 to further cool the working fluid. This is conducive to the working fluid quickly cooling the signal detection component 11, so as to achieve the effect of improving the utilization rate of the refrigeration working fluid and reducing consumption.

[0056] In one possible embodiment, the cooling circulation system 2 further includes a dewar 26, within which a precooler 22, a first-stage cold head 24, a second-stage cold head 25, and a JT throttle 123 are disposed. A working fluid circulation pump 21 and a helium compressor 23 are disposed externally. The nuclear magnetic resonance probe 1 further includes a flange joint 16 and a housing 15. The housing 15 is hollow and has a receiving chamber. The signal detection assembly 11 and the capillary evaporator 121 are disposed in the receiving chamber. The housing 15 is detachably connected to the dewar 26 via the flange joint 16.

[0057] In this embodiment, the Dewar tank 26 forms a vacuum environment by evacuating the air to reduce heat transfer, reduce the temperature rise of the precooler 22, the first-stage cold head 24, the second-stage cold head 25 and the JT throttle 123, which is beneficial to improving the cooling efficiency of the working fluid, thereby improving the utilization rate of the working fluid and reducing consumption.

[0058] In a possible implementation, the cooling circulation system 2 further includes a vacuum connector 27 , which is used to connect the Dewar tank 26 and a working medium circulation pipe 122 extending to the outside.

[0059] In this embodiment, the medium-pressure, medium-temperature refrigerant in the cooling circulation system 2 is initially pressurized in the refrigerant circulation pump 21 to a high-temperature, high-pressure refrigerant. The refrigerant is then cooled in the precooler 22 to a high-pressure, medium-temperature refrigerant. The refrigerant then passes through the first-stage cold head 24 and the second-stage cold head 25 to a high-pressure, low-temperature refrigerant. The refrigerant is then transported through the refrigerant circulation pipeline 122 to the JT throttle 123. Due to the JT effect, the outflowing refrigerant is reduced to a low-pressure, ultra-low-temperature state. The refrigerant then passes through the Tesla valve to accelerate its flow rate before flowing to the capillary evaporator 121. The refrigerant in the capillary evaporator 121 acts as a cold source to cool the probe signal detection assembly 11. After absorbing heat from the probe signal detection assembly 11, the refrigerant is converted to a medium-temperature, medium-pressure refrigerant. The refrigerant then returns to the compressor through the refrigerant circulation pipeline 122, completing a refrigeration cycle.

[0060] The precooler 22, first-stage cold head 24, second-stage cold head 25, first Tesla valve 13, second Tesla valve 14, JT throttle 123, and a portion of the working fluid circulation piping 122 are located within the dewar 26, which is a vacuum environment. The capillary evaporator 121 and signal detection assembly 11 are located within the housing 15, which is also a vacuum environment. The working fluid circulation piping 122 extending from the dewar 26 is connected via a vacuum connector 27 to ensure that the vacuum environment within the dewar 26 is not disrupted. Furthermore, to facilitate rapid disassembly and installation of the probe, a flange connector 16 is used to connect the dewar 26 to the probe housing 15.

[0061] The above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that any modification or equivalent replacement of the technical solutions of the present application should not depart from the spirit and scope of the technical solutions of the present application.

Claims

1. A probe for nuclear magnetic resonance, characterized in that: include: A signal detection component for detecting nuclear magnetic resonance signals; A cooling assembly comprising a capillary evaporator, a working fluid circulation pipe, and a JT throttle. The capillary evaporator is bonded to the signal detection assembly to cool the signal detection assembly. One end of the working fluid circulation pipe is connected to the inlet end of the capillary evaporator, and the other end is connected to the outlet end of the capillary evaporator. The JT throttle is disposed in the working fluid circulation pipe near the inlet end of the capillary evaporator. The JT throttle is used to reduce the pressure of the working fluid at the inlet end of the capillary evaporator to further cool the working fluid. The JT throttle comprises a first connecting portion, a pressure reducing portion, and a second connecting portion that are connected in sequence. The first connecting portion is connected to the working medium circulation pipeline. The inner diameter of the pressure reducing portion is smaller than the inner diameter of the first connecting portion. The working medium in the working medium circulation pipeline flows from the first connecting portion into the pressure reducing portion to reduce the pressure and temperature of the working medium. The second connecting portion is used to output the refrigerant to the capillary tube evaporator. The pressure reducing part includes a first through hole and a second through hole, one end of the first through hole is connected to the first connection part, and the other end is connected to the second through hole, the inner diameters of the first connection part, the inner diameters of the first through hole and the inner diameters of the second through hole decrease successively, and the second through hole is connected to the second connection part; there are multiple second through holes, and the multiple second through holes are arranged in parallel, and the first through hole is connected to the second connection through the multiple second through holes.

2. The probe for nuclear magnetic resonance according to claim 1, characterized in that: The probe for nuclear magnetic resonance also includes a first Tesla valve, one end of which is connected to the second connection part of the JT throttle and the other end is connected to the inlet end of the capillary evaporator. The first Tesla valve is used to increase the flow rate of the refrigerant.

3. The probe for nuclear magnetic resonance according to claim 1 or 2, characterized in that: The probe for nuclear magnetic resonance further includes a second Tesla valve, which is arranged at the outlet end of the capillary evaporator.

4. The probe for nuclear magnetic resonance according to claim 1, characterized in that: The capillary evaporator includes a plurality of bent portions, and the plurality of bent portions are used to increase a contact area with the signal detection component.

5. The probe for nuclear magnetic resonance according to claim 1, characterized in that: The probe for nuclear magnetic resonance further comprises a shell, which is hollow and has a receiving chamber. The signal detection component and the capillary evaporator are arranged in the receiving chamber. The shell is detachably connected to the working medium circulation pipeline.

6. A cooling circulation system, characterized in that: include: a working fluid circulation pump, connected to the working fluid circulation pipeline, and configured to pressurize the working fluid; A precooler is connected to the output end of the working medium circulation pump, and is used to precool the pressurized working medium; A cold head assembly, comprising a helium compressor, a first-stage cold head, and a second-stage cold head. The helium compressor is connected to the first-stage cold head and the second-stage cold head, respectively, and is used to cool the first-stage cold head and the second-stage cold head. The first-stage cold head and the second-stage cold head are spaced apart from each other in the working fluid circulation pipeline to cool the pre-cooled working fluid. The probe for nuclear magnetic resonance according to any one of claims 1 to 5, wherein the JT throttle is used to reduce the pressure of the cooled working fluid to further cool the working fluid.

7. The cooling circulation system according to claim 6, characterized in that: The cooling circulation system further comprises a dewar tank, wherein the precooler, the first-stage cold head, the second-stage cold head and the JT throttle are arranged inside the dewar tank, and the working medium circulation pump and the helium compressor are arranged outside the dewar tank; The probe for nuclear magnetic resonance further includes a flange joint and a shell. The shell is hollow and has a accommodating chamber. The signal detection component and the capillary evaporator are arranged in the accommodating chamber. The shell is detachably connected to the Dewar tank through the flange joint.

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