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研制了ＥＰＲ低温现场装置（７７－３００Ｋ），使用开槽缝的良好绝热材料聚四氟乙烯薄膜包裹谐振腔内的石英套管并用室温氮气吹扫，以免凝结水气，使微波电磁场能在满足电磁场边界条件下有效地进入样品管内；低温现场装置使用石英管、宽口杜瓦瓶和传热效果良好的螺旋铜管为主要制作材料，改变吹扫样品管的氮冷气流速以调节所需的实验温度。该装置有效克服了目前ＥＰＲ低温实验通用装置－指型石英杜瓦液氮温度实验装置和氦循环封闭致冷实验装置的局限性：液氮沸腾翻滚、制作材料昂贵和制作工艺复杂等。该装置应用于ＶＭｇＯ体系催化剂活性位的低温现场检测，获得了较为理想的实验结果。
The EPR cryogenic field device (77-300K) was developed. Teflon film with a slotted slot was used to encase the quartz sleeve in the resonator and purged with nitrogen at room temperature to prevent the condensation of moisture and the microwave electromagnetic field. Electromagnetic field boundary conditions effectively enter the sample tube; low-temperature field devices using quartz tube, wide mouth dewar and good heat transfer effect of the spiral copper tube as the main production material, change the nitrogen gas purge sample tube flow rate to adjust the required Experimental temperature. The device effectively overcomes the limitations of the current EPR low temperature universal device - finger-type quartz Dewar liquid nitrogen temperature experimental device and the helium cycle closed refrigeration experimental device: liquid nitrogen boiling tumbling, expensive materials and the production process is complex and so on. The device is applied to the low-temperature on-site detection of catalyst active sites in VMgO system, and the ideal experimental result is obtained.