Abstract: A measuring method of determining component concentration in a solution by calculating component concentrations in the solution at various temperatures in a small number of steps. The component concentration is measured at an arbitrary temperature T by using a solution absorbance spectrum and solvent absorbance spectrum at a plurality of wavelength(s)r, and preliminarily determining a calibration coefficient Mij (TO). Concentration of Ci of component i in solution at reference temperature TO, is obtained at differential spectrum of solution spectrum S (?j, T) at temperature T in j-th wavelength ?j and solvent spectrum B (?j, T) at temperature T in j-th wavelength ?j, calculating calibration coefficient Mij (TO) the specific component concentrations.

Abstract: A measuring method of determining component concentration in a solution by calculating component concentrations in the solution at various temperatures in a small number of steps. The component concentration is measured at an arbitrary temperature T by using a solution absorbance spectrum and solvent absorbance spectrum at a plurality of wavelength(s)r, and preliminarily determining a calibration coefficient Mij (TO). Concentration of Ci of component i in solution at reference temperature TO, is obtained at differential spectrum of solution spectrum S (?j, T) at temperature T in j-th wavelength ?j and solvent spectrum B (?j, T) at temperature T in j-th wavelength ?j, calculating calibration coefficient Mij (TO) the specific component concentrations.

Abstract: A fine particle measuring system for semiconductor cleaning fluid includes a sample tank for holding a sample of the cleaning fluid and a pump that can circulate the sample of cleaning fluid. A return conduit is connected to a filter and a bubble discharge opening member to return a major portion of the sample of cleaning fluid to the sample tank. A minor portion of the cleaning fluid is directed respectively to a cooling unit, and then to a deaerator for eliminating any effects of bubbles on the measurement of fine particles in the cleaning fluid. A first conduit is connected to a measuring cell to return the sample cleaning fluid to the sample tank while a second conduit is connected to the deaerator to draw gas from the bubbles that have been separated from the deaerator.