Patent ID: 6595036
Filing Date: 2003-07-22
Classification: G01N

Abstract:
A method for measuring an amount of a gas adsorbed on a solid sample, the method comprising:a preparatory process which comprises the steps of: preliminarily determining a dead volume of a reference cell for determination of a dead volume of a sample cell which retains the solid sample and, at this time point, filling and confining the gas in the reference cell; measuring an initial dead volume of the sample cell and an initial internal gas pressure of the reference cell with the sample cell and the reference cell being immersed in a cryogenic coolant contained in a constant temperature bath; and calculating an initial dead volume of the reference cell at a time point of the measurement of the initial dead volume of the sample cell on the basis of the initial internal gas pressure of the reference cell and the preliminarily measured dead volume of the reference cell; and a gas adsorption determining process which comprises the steps of: feeding the gas into a reference volume portion having a known geometric volume with the sample cell and the reference cell being immersed in the cryogenic coolant within the constant temperature bath, and measuring an internal gas pressure of the reference volume portion; allowing the reference volume portion to communicate with the sample cell to introduce the gas from the reference volume portion into the sample cell, and measuring an internal gas pressure of the sample cell; and calculating the amount of the gas adsorbed on the solid sample on the basis of the internal gas pressure of the reference volume portion, the internal gas pressure of the sample cell and the dead volume of the sample cell, wherein the dead volume of the sample cell to be employed for the calculation of the amount of the gas adsorbed on the solid sample is determined in the gas adsorption determining process by measuring an internal gas pressure of the reference cell at a time point of the measurement of the internal gas pressure of the sample cell, and correcting the initial dead volume of the sample cell on the basis of the internal gas pressure of the reference cell measured at the time point of the measurement of the internal gas pressure of the sample cell, the initial dead volume of the reference cell and the initial internal gas pressure of the reference cell.