Helium circulation low-temperature constant-temperature system for paramagnetic resonance spectrometer

Abstract

The invention discloses a helium circulating low-temperature constant-temperature system for a paramagnetic resonance spectrometer. The helium circulating low-temperature constant-temperature system comprises a gas storage tank, a refrigeration unit, a variable-temperature constant-temperature cavity and a circulating pump, the gas storage tank is used for storing high-purity helium; the refrigeration unit is connected with the gas storage tank, high-purity helium in the gas storage tank enters the refrigeration unit under the action of positive pressure in the gas storage tank, and the refrigeration unit is used for cooling the high-purity helium entering the refrigeration unit and discharging low-temperature high-purity helium; the variable-temperature constant-temperature cavity is connected with the refrigeration unit and used for receiving low-temperature high-purity helium discharged by the refrigeration unit, and the low-temperature high-purity helium flows through a sample area in the variable-temperature constant-temperature cavity to refrigerate the sample area and then is discharged from the variable-temperature constant-temperature cavity; and the circulating pump is used for conveying the high-purity helium discharged from the temperature-variable and constant-temperature cavity into the gas storage tank. According to the invention, cyclic utilization of helium is realized, the cost is reduced, and long-time stable operation can be realized.

Description

technical field [0001] The invention relates to the technical field of paramagnetic resonance spectrometers, in particular to a helium circulation cryogenic constant temperature system for paramagnetic resonance spectrometers. Background technique [0002] The cryostat system is one of the important devices in the electron paramagnetic resonance (EPR) spectrometer, which is used to provide a controllable low temperature environment for the sample. The traditional EPR spectrometer cryogenic system is a continuous flow mode, such as the patent CN208110408U, by pressing the liquid nitrogen or liquid helium in the external Dewar into the cryostat, so that the liquid helium or liquid nitrogen flows through the vicinity of the sample tube to process the sample. Cool down. In this type of device, liquid nitrogen or liquid helium will be discharged into the atmosphere from the exhaust port of the thermostat after flowing through the sample, which requires continuous consumption of ...

AI Technical Summary

Problems solved by technology

In this type of device, liquid nitrogen or liquid helium will be discharged into the atmosphere from the exhaust port of the thermostat after flowing through the sample, which requires continuous consumption of liquid nitrogen or liquid helium

Liquid nitrogen and liquid helium are expensive, difficult to obtain, unstable in supply, and limited Dewar capacity makes it difficult to perform long-term continuous measurement

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