| 摘要 |
PURPOSE:To perform measurement highly sensitively while liquid sample is allowed to flow to a cell by using a small capacity cell in opto-acoustic measurement. CONSTITUTION:A duct with low rigidity such as a vinyl tube is used as a duct connected to at least one of a branch tube 28 for a cell 15 inlet and a branch tube 29 for an outlet. Alternately, difference in acoustic impedance is made between inside and outside by providing an aperture part instead of uniform inner diameters of the branch tubes 28,29. Thus sound speed drops in the cell so that frequency of a resonance peak in the cell is lower than a structural resonance peak of a detector 4 or the cell, whereby highly sensitive measurement is possible without influence from opening of the inlet and outlet provided for permitting sample solution to flow during measurement. |
