Low-temperature thermostat system adaptive to pulse electron paramagnetic resonance spectrometer

Abstract

The utility model discloses a cryostat system adaptive to a pulse electron paramagnetic resonance spectrometer, which comprises a cryostat component and a low-loss infusion tube component, and one end of the cryostat component is fixedly mounted with one end of the low-loss infusion tube component. According to the cryostat system adaptive to the pulse electron paramagnetic resonance spectrometer, the pulse electron paramagnetic resonance spectrometer can be used for experiments in a low-temperature environment, liquid helium / liquid nitrogen is adopted to directly refrigerate a sample, experiment conditions in the low-temperature environment are realized, the external diameter of a 62mm electromagnet gap is adapted to be smaller than or equal to 50mm through compact design, sufficient sample space is reserved, and the experiment efficiency is improved. The modularized interface supports rapid disassembly and assembly and function expansion, direct liquid helium / liquid nitrogen refrigeration, the cooling rate is increased by 30%, the temperature control precision reaches + / -0.1 K, vacuum insulation and a cold shield cooperate to reduce heat loss, the modularized interface is compatible with a mainstream pulse EPR probe, and the effect of a variable temperature experiment is supported.

Description

Technical Field

[0001] This application relates to the field of low-temperature experimental apparatus, and in particular to a cryostat system adapted for pulsed electron paramagnetic resonance spectrometers. Background Technology

[0002] With advancements in science and technology, electron spin resonance (ESR) allows us to understand the state of unpaired electrons and their surrounding environment in matter without damaging the sample, thus providing information about the material's structure. Temperature affects the spin state of matter, and low temperatures weaken the interaction between electron spin and its environment. Furthermore, the energy level spacing of electron spin transitions increases at low temperatures, making the test signal clearer and stronger, which is beneficial for obtaining more accurate structural information. Therefore, low temperature is the preferred method for most ESR experiments.

[0003] Because the low-temperature equipment with the sample needs to be placed into the 62mm gap of the electromagnet during testing, the outer diameter of the low-temperature equipment is usually small. If sufficient space for the sample is required, the sample tube design must be simplified. Currently, the low-temperature systems on the market that are compatible with electron paramagnetic resonance spectrometers have relatively bulky structures and poor performance indicators. High-performance systems are mainly imported products. Utility Model Content

[0004] To address the technical issues of existing low-temperature systems adapted to electron paramagnetic resonance spectrometers having relatively bulky structures and poor performance, this invention proposes a low-temperature thermostat system adapted to pulsed electron paramagnetic resonance spectrometers.

[0005] This application provides a cryostat system adapted for pulsed electron paramagnetic resonance spectrometers, employing the following technical solution:

[0006] A cryostat system adapted to a pulsed electron paramagnetic resonance spectrometer includes a cryostat assembly and a low-loss infusion tubing assembly, wherein one end of the cryostat assembly is fixedly installed with one end of the low-loss infusion tubing assembly.

[0007] Optionally, the cryogenic thermostat assembly includes a cryogenic thermostat, an EPR pulse probe, a vacuum power supply, an infusion tube inlet, a vacuum extraction port, a vacuum chamber glass window, a negative pressure gas extraction port, a cryogenic medium inlet, a cold shield, a return gas pipe, a thermometer, a heat exchanger, and a heater.

[0008] Optionally, the low-loss infusion tubing assembly includes a liquid nitrogen / liquid helium infusion tubing, an infusion tubing fixing nut, a helium outlet, and a liquid nitrogen / liquid helium infusion tubing control valve.

[0009] Optionally, one end of the EPR pulse probe is fixedly mounted on the outer surface of the cryogenic thermostat using a standard KF50 connector; one end of the electrical connector of the vacuum power supply is fixedly mounted on the outer surface of the thermometer; one end of the signal line of the heater is fixedly welded to one end of the pin of the vacuum power supply; one end of the infusion tube inlet is fixedly mounted on one end of the liquid nitrogen / liquid helium infusion tube; one end of the vacuum evacuation port is fixedly mounted on the outer surface of the cryogenic thermostat via a vacuum pump assembly to evacuate the gas inside the cryogenic thermostat; the outer surface of the vacuum chamber is fixedly mounted on the outer surface of the cryogenic thermostat; and the lower surface of the vacuum chamber is fixedly mounted on one end of the glass window.

[0010] Optionally, one end of the cryogenic thermostat is fixedly installed to one end of the infusion tube fixing nut, the other end of the infusion tube fixing nut is fixedly installed to one end of the liquid nitrogen / liquid helium infusion tube, one end of the cryogenic thermostat is fixedly installed to one end of the cryogenic medium inlet, the interior of the cryogenic thermostat is fixedly installed to the outer surface of the cold shield, the return gas pipe is fixedly installed inside the cryogenic thermostat, the thermometer is fixedly installed inside the cryogenic thermostat, the heat exchanger is fixedly installed inside the cryogenic thermostat, and the heater is fixedly installed inside the cryogenic thermostat.

[0011] Optionally, one end of the liquid nitrogen / liquid helium delivery pipe is fixedly installed to one end of the helium outlet, and the control valve of the liquid nitrogen / liquid helium delivery pipe is located at one end of the liquid nitrogen / liquid helium delivery pipe.

[0012] In summary, this application includes at least one of the following beneficial technical effects:

[0013] By setting up a cryostat system adapted to pulsed electron paramagnetic resonance (EPR) spectrometers, the system enables PER experiments in low-temperature environments. It utilizes direct liquid helium / liquid nitrogen to cool samples, achieving the necessary low-temperature experimental conditions. The compact design accommodates a 62mm electromagnet with a slit outer diameter ≤50mm, providing ample sample space. The modular interface supports rapid assembly and disassembly and functional expansion. Direct liquid helium / liquid nitrogen cooling increases the cooling rate by 30%, achieving temperature control accuracy of ±0.1K. Vacuum insulation and a cold shield work together to reduce heat loss. It is compatible with mainstream pulsed EPR probes and supports variable-temperature experiments. This system solves the technical problems of existing commercially available cryogenic systems adapted to EPR spectrometers, which are relatively bulky and have poor performance. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a cryostat system adapted to a pulsed electron paramagnetic resonance spectrometer proposed in this utility model.

[0015] Figure 2A three-dimensional view of the vacuum cavity structure of a cryogenic thermostat system adapted to a pulsed electron paramagnetic resonance spectrometer proposed in this utility model.

[0016] Figure 3 This is a perspective view of a heat exchanger structure adapted to a low-temperature thermostat system for a pulsed electron paramagnetic resonance spectrometer, as proposed in this utility model.

[0017] In the diagram: 1. Cryogenic thermostat; 2. Liquid nitrogen / liquid helium infusion tubing; 3. Infusion tubing fixing nut; 4. Helium outlet; 5. EPR pulse probe; 6. Vacuum electrical feedthrough; 7. Infusion tubing inlet; 8. Vacuum extraction port; 9. Vacuum chamber; 10. Glass window; 11. Negative pressure gas extraction port; 12. Cryogenic medium inlet; 13. Cold shield; 14. Return gas pipe; 15. Thermometer; 16. Heat exchanger; 17. Heater; 18. Liquid nitrogen / liquid helium infusion tubing control valve. Detailed Implementation

[0018] The following is in conjunction with the appendix Figures 1-3 This application will be described in further detail.

[0019] Reference Figures 1-3 A cryogenic thermostat 1 system adapted to a pulsed electron paramagnetic resonance spectrometer, comprising a cryogenic thermostat 1 component and a low-loss infusion tubing component, wherein one end of the cryogenic thermostat component is fixedly installed with one end of the low-loss infusion tubing component.

[0020] Specifically, the low-temperature thermostat assembly includes a low-temperature thermostat 1, an EPR pulse probe 5, a vacuum power supply 6, an infusion tube inlet 7, a vacuum extraction port 8, a vacuum chamber 9, a glass window 10, a negative pressure gas extraction port 11, a low-temperature medium inlet 12, a cold shield 13, a return gas pipe 14, a thermometer 15, a heat exchanger 16, and a heater 17.

[0021] Specifically, the low-loss infusion tubing assembly includes a liquid nitrogen / liquid helium infusion tubing 2, an infusion tubing fixing nut 3, a helium outlet 4, and a liquid nitrogen / liquid helium infusion tubing control valve 18.

[0022] Specifically, the EPR pulse probe 5 is fixedly installed on the outer surface of the cryogenic thermostat 1 using a standard KF50. One end of the electrical connector of the vacuum power supply 6 is fixedly installed on the outer surface of the thermometer 15. One end of the signal line of the heater 17 is fixedly welded to one end of the pin of the vacuum power supply 6. One end of the infusion tube inlet 7 is fixedly installed on one end of the liquid nitrogen and liquid helium infusion tube 2. One end of the vacuum evacuation port 8 is fixedly installed on the outer surface of the cryogenic thermostat 1 through a vacuum pump assembly to evacuate the gas inside the cryogenic thermostat 1. The outer surface of the vacuum chamber 9 is fixedly installed on the outer surface of the cryogenic thermostat 1. The lower surface of the vacuum chamber 9 is fixedly installed on one end of the glass window 10.

[0023] Specifically, one end of the cryogenic thermostat 1 is fixedly installed with one end of the infusion tube fixing nut 3, the other end of the infusion tube fixing nut 3 is fixedly installed with one end of the liquid nitrogen / liquid helium infusion tube 2, one end of the cryogenic thermostat 1 is fixedly installed with one end of the cryogenic medium inlet 12, the interior of the cryogenic thermostat 1 is fixedly installed with the outer surface of the cold shield 13, the return gas pipe 14 is fixedly installed inside the cryogenic thermostat 1, the thermometer 15 is fixedly installed inside the cryogenic thermostat 1, the heat exchanger 16 is fixedly installed inside the cryogenic thermostat 1, and the heater 17 is fixedly installed inside the cryogenic thermostat 1.

[0024] Specifically, one end of the liquid nitrogen-liquid helium infusion pipe 2 is fixedly installed at one end of the helium outlet 4, and the liquid nitrogen-liquid helium infusion pipe control valve 18 is set at one end of the liquid nitrogen-liquid helium infusion pipe 2.

[0025] By setting up a cryostat system adapted to pulsed electron paramagnetic resonance (EPR) spectrometers, the system enables PER experiments in low-temperature environments. It utilizes direct liquid helium / liquid nitrogen to cool samples, achieving the necessary low-temperature experimental conditions. The compact design accommodates a 62mm electromagnet with a slit outer diameter ≤50mm, providing ample sample space. The modular interface supports rapid assembly and disassembly and functional expansion. Direct liquid helium / liquid nitrogen cooling increases the cooling rate by 30%, achieving temperature control accuracy of ±0.1K. Vacuum insulation and a cold shield 13 work together to reduce heat loss. It is compatible with mainstream pulsed EPR probes and supports variable-temperature experiments. This system solves the technical problems of existing cryogenic systems adapted to EPR spectrometers, which are relatively bulky and have poor performance.

[0026] Working principle: First, insert the liquid nitrogen / liquid helium inlet tube 2 into the liquid nitrogen / liquid helium Dewar. Then, extract the air from the cryogenic thermostat 1 through the vacuum evacuation port 8. Next, connect the liquid nitrogen / liquid helium inlet tube 2 to the cryogenic thermostat 1 through the inlet tube fixing nut 3. At this time, open the liquid nitrogen / liquid helium inlet tube control valve 18. Liquid nitrogen and liquid helium flow into the heat exchanger 16 through the cryogenic medium inlet 12 for heat exchange, and then flow to the EPR pulse probe 5 for cooling until the EPR pulse probe 5 is cooled to the liquid nitrogen / liquid helium temperature. After heat exchange, the cryogenic helium gas is discharged into the atmosphere through the helium outlet 4.

[0027] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An adapted pulse electron paramagnetic resonance spectrometer cryostat system, characterized by: It includes a cryogenic thermostat assembly and a low-loss infusion tubing assembly, with one end of the cryogenic thermostat assembly fixedly installed to one end of the low-loss infusion tubing assembly.

2. The adapted pulse electron paramagnetic resonance spectrometer cryostat system of claim 1, wherein: The cryogenic thermostat assembly includes a cryogenic thermostat (1), an EPR pulse probe (5), a vacuum power supply (6), an infusion tube inlet (7), a vacuum extraction port (8), a vacuum chamber (9), a glass window (10), a negative pressure gas extraction port (11), a cryogenic medium inlet (12), a cold shield (13), a return gas pipe (14), a thermometer (15), a heat exchanger (16), and a heater (17).

3. The adapted pulse electron paramagnetic resonance spectrometer cryostat system of claim 2, wherein: The low-loss infusion tubing assembly includes a liquid nitrogen / liquid helium infusion tubing (2), an infusion tubing fixing nut (3), a helium outlet (4), and a liquid nitrogen / liquid helium infusion tubing control valve (18).

4. The adapted pulse electron paramagnetic resonance spectrometer cryostat system of claim 3, wherein: The EPR pulse probe (5) is fixedly installed on the outer surface of the cryogenic thermostat (1) using a standard KF50. One end of the electrical connector of the vacuum power supply (6) is welded to the lead extension of the thermometer (15). One end of the signal line of the heater (17) is fixedly welded to one end of the pin of the vacuum power supply (6). One end of the liquid nitrogen and liquid helium infusion tube (2) is inserted into one end of the infusion tube socket (7) and fixedly installed. One end of the vacuum evacuation port (8) is fixedly installed on the outer surface of the cryogenic thermostat (1) and then the gas in the cryogenic thermostat (1) is evacuated by a vacuum pump group. The outer surface of the vacuum chamber (9) is fixedly installed on the inner and outer surfaces of the cryogenic thermostat (1). The lower surface of the vacuum chamber (9) is sealed and fixedly installed on one end of the glass window (10).

5. The adapted pulse electron paramagnetic resonance spectrometer cryostat system of claim 4, wherein: One end of the cryogenic thermostat (1) is fixedly installed with one end of the infusion tube fixing nut (3), the other end of the infusion tube fixing nut (3) is fixedly installed with one end of the liquid nitrogen and liquid helium infusion tube (2), one end of the cryogenic thermostat (1) is fixedly installed with one end of the cryogenic medium inlet (12), the interior of the cryogenic thermostat (1) is fixedly installed with the outer surface of the cold shield (13), the return gas pipe (14) is fixedly installed inside the cryogenic thermostat (1), the thermometer (15) is fixedly installed inside the cryogenic thermostat (1), the heat exchanger (16) is fixedly installed inside the cryogenic thermostat (1), and the heater (17) is fixedly installed inside the cryogenic thermostat (1).

6. The adapted pulse electron paramagnetic resonance spectrometer cryostat system of claim 5, wherein: One end of the liquid nitrogen-liquid helium infusion tube (2) is fixedly installed at one end of the helium outlet (4), and the control valve (18) of the liquid nitrogen-liquid helium infusion tube is located at one end of the liquid nitrogen-liquid helium infusion tube (2).

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