Horiba, Ltd.

Masaru Inoue

Juichiro Ukon

Issei Yokoyama

Takashi Hagiwara

An analytical method capable of easily, rapidly, and accurately determining concentrations of a multi-component aqueous solution. Near-infrared spectra of a standard solution containing k components of known concentrations are measured n times within a range of 1,500 to 1,850 nm. A loading matrix of p columns by m rows and an intermediate matrix of k columns by m rows for an appointed factor number m are obtained from a response matrix of p columns by n rows consisting of p absorbance values of the respective spectra in a calibration stage and p absorbance values of a near-infrared spectrum within a wavelength range of 1,500 to 1,850 nm of a test liquid. The test liquid contains k components including pure water of unknown concentrations. The concentrations of the k components are determined from a group of absorbance values and the loading and intermediate matrices obtained in the calibration stage by a matrix operation in an prediction stage. In the calibration stage, k+1 characteristic contents can be obtained by adding a solution temperature as one of characteristic items, and k concentration values and one temperature value can be obtained in the prediction stage.

Analytical method for multi-component aqueous solutions and apparatus

A method of analyzing the concentration of components in a fluid solution that can be contaminated with gas bubbles includes applying a spectrum of light to a test cell holding a sample fluid solution and detecting the measurement of the intensity of light passing through the test cell. A gas of the type that would be found in the sample fluid solution can be initially inserted into the test cell with light of a predetermined range of wavelengths scanning the test cell to obtain a reference spectrum. The test cell is then filled with the sample fluid solution and the light measurement is again conducted to obtain a sample spectrum. Data processing can occur to derive a light absorbance spectrum from the reference spectrum and sample spectrum to enable a determination of the percentage of concentrations of each component from the light absorbance spectrum, including the percentage of gas. Adding the determined percentages of concentration will provide a total amount, and comparing this total amount with a predetermined value can verify the accuracy of the concentration of components. If the data is contaminated as a result of an excess presence of gas bubbles, this data can be discarded to insure that the proper amount of concentrations is determined.

Method of analyzing the concentration of components in a solution

A wavelength-scanning mechanism for a spectrometer utilizes an eccentric disc cam driven by a pulse motor to pivot a diffraction grating with a contact bar fixed thereto. A light source supplies light to the mechanism with a first concave spherical mirror reflecting light to the diffraction grating and reflecting light reflected by the diffraction grating to a zero-order light detector. A second concave spherical mirror reflects light diffracted by the diffraction grating to a diffracted light detector. A controller receives information from the light detectors and controls the pulse motor. At least one cam follower is mounted on the cam at a position eccentric from the rotational axis thereof and slidably contacts the contact bar. Alternatively, the diffraction grating has two contact bars fixed thereto, and the cam follower is pivoted between the contact bars. A method of utilizing the mechanism first determines a center value of zero-order light reflected by the diffraction grating by pivoting the diffraction grating in steps between the time zero-order light is detected until it is no longer detected. The number of steps is divided by two, which yields the center value. Diffracted light is detected at the center value, and the spectral intensity of the detected diffracted light is calculated.

Growing community of inventors

Miyanohigashi-machi, Japan

Masaru Inoue