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After a gas leak occurs, if not detected in a timely manner, it poses a significant threat to people's lives and property. To ensure the safe transportation and use of natural gas, and to protect natural gas users and maintenance, the content of tetrahydrothiophene added to the natural gas pipeline needs to be regularly analyzed and assessed using analyzers. Our company's portable gas tetrahydrothiophene UV analysis system mainly consists of a preprocessing system, UV spectrometer, optical gas measurement cell, UV light source, and algorithms, featuring automatic calibration for temperature deviation, stable detection data, and sensitive response speed.