基于STM32的腔衰荡光谱 CO₂ 传感器及其在种子呼吸过程的应用

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STM32-based cavity ring-down spectroscopy CO2 Sensor and its application in seed respiration

LI Haokai， ZHAI Baojie，WANG Mengyuan， ZHOU Yueting，GUO Guqing，QIU Xuanbing，LI Chuanliang

（College of applied science， Taiyuan University of Science and Technology，Shanxi Precision Measure ment and Online Testing Equipment Engineering Research Center， Taiyuan O3O024， China） * Corresponding author， E -mail： clli@tyust. edu. cn

Abstract： The analysis of the seed respiration process is of critical importance for accurately assessing seed viability. Therefore，the development of a rapid，stable，and highly sensitive seed respiration detection device is essential. In this study，a CO2 gas sensor was designed and constructed based on an STM32 microcontroler and Cavity Ring-Down Spectroscopy （CRDS） technology，and it was subsequently applied to seed respiration detection. The sensor employed an STM32-based control and data acquisition scheme，comprising a threshold detection and shut-off module formed by a high-speed comparator and RS flip-flop，a high-speed analog signal acquisition module，an STM32 master control unit，and an upper computer data processing system. The threshold detection module achieved a cutoff delay of 0.45μs ， while the maximum sampling rate of the analog signal acquisition module reached 31.25MHz .Experimental verification confirmed that the sensor can detect CO2 concentrations as low as 1.5ppm ，demonstrating good sensitivity. The sensor successfully captured the respiration process of rice seeds，producing a curve of CO2 concentration changes over time for 10g of rice seeds.Within 2.5 hours，the CO2 concentration increased by approximately 730ppm . This study highlights the potential and application value of CRDS technology in seed respiration detection.

Key words： cavity ring-down spectroscopy； STM32；carbon dioxide；seed respiratio

1引言

种子呼吸是种子获取生命活动所需能量的基本生物学过程[1-2]。（剩余15144字）