Patent ID: 11885741
Assignee: YOKOGAWA ELECTRIC CORPORATION
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 2:
3. A property analysis method used by an analysis device, the property analysis method comprising:
measuring an absorbance spectrum of liquefied gas using near-infrared spectroscopy;
calculating a property value of the liquefied gas from a calibration curve representing a relationship between a property value and an absorbance spectrum of sample gas and a measurement result of the absorbance spectrum of the liquefied gas, the calibration curve being generated from a measurement result of the absorbance spectrum of the sample gas obtained for each property value as a result of injecting the sample gas into a container, liquefying the sample gas in the container, measuring the absorbance spectrum of the sample gas in a liquefied state by a near-infrared measuring instrument via a near-infrared probe extending from inside to outside the container, and using a plurality of samples that differ in property value as the sample gas;
measuring a temperature of the liquefied gas; and
calculating the property value of the liquefied gas from, as the calibration curve, a calibration curve representing a relationship among the property value, a temperature, and the absorbance spectrum of the sample gas and the measurement result of the absorbance spectrum of the liquefied gas and a measurement result of the temperature of the liquefied gas, the calibration curve being generated from the measurement result of the absorbance spectrum of the sample gas obtained for each combination of the property value and the temperature as a result of measuring the temperature of the sample gas in the liquefied state, using the plurality of samples that differ in property value as the sample gas, and changing the temperature of the sample gas in the liquefied state.