Abstract: Information used for creating an adsorption isostere of a substance to be measured in a measuring system (container) is obtained by repeating alternately a first control step of changing temperature or pressure of the measuring system by a fixed amount by adjusting a gas amount supplied to/discharged from the measuring system, and a second control step of changing pressure or temperature of the measuring system by adjusting the gas amount supplied to/discharged from the measuring system until a gas adsorption amount of the substance to be measured becomes the same as before execution of the first control step.

Abstract: Information used for creating an adsorption isostere of a substance to be measured in a measuring system (container) is obtained by repeating alternately a first control step of changing temperature or pressure of the measuring system by a fixed amount by adjusting a gas amount supplied to/discharged from the measuring system, and a second control step of changing pressure or temperature of the measuring system by adjusting the gas amount supplied to/discharged from the measuring system until a gas adsorption amount of the substance to be measured becomes the same as before execution of the first control step.

Abstract: In a volumetric gas adsorption measuring method, an initial dead volume of the sample cell and an initial dead volume of a reference cell at the same time point are preliminarily determined. When the gas adsorption on the solid sample is to be measured, a change in the dead volume of the sample cell is calculated on the basis of an internal gas with the sample cell and reference cell immersed in a pressure of the reference cell measured at this time point cryogenic fluid temperature bath, the initial dead volume of the reference cell, and an initial gas pressure of the reference cell measured at a time point of the measurement of the initial dead volume of the reference cell. Then, the initial dead volume of the sample cell preliminarily measured is corrected on the basis of the change in the dead volume of the sample cell for the calculation of the amount of the gas adsorbed on the solid sample.