Horiba, Ltd.

Kaori Inoue

Masayuki Adachi

Yutaka Yamagishi

Kenji Takeda

Masaru Miyai

Masaaki Ishihara

The present invention provides a multi-component gas analyzing method using FTIR, which can correct for an influence of a coexistent gas due to an intensity change in the spectrum itself that occurs depending on the base gas composition so that it is possible to carry out, a measurement with high precision. A plurality of components in a sample are quantitatively analyzed based upon an absorption spectrum obtained by FTIR. After having calculated multi-component concentrations from a mixed gas spectrum by using a quantitative algorithm, calculations are further carried out so as to correct for a change in spectrum due to a coexistent gas component with respect to part of target components.

Multi-component gas analyzing method using FTIR

In analyzing the concentration of an objective component contained in a sample gas by a gas analyzer, an output of the gas analyzer is corrected at a fixed point by applying the relationship between the concentration of a coexistent gas and a span sensitivity of the objective component to make it possible to simply correct the effect of the coexistent gas. In addition, by inputting, at the time of the calibration of the gas analyzer, the information on to what extent the base gas composition differs from the average amount of the actual sample along with the concentration amount of the objective component in the calibration gas, the sensitivity adjustment coefficient is determined by taking into account the effect amount which is previously stored in the gas analyzer, by which the effect amount of the span sensitivity by the difference of the base gas compositions in the calibration gas and the sample gas is suppressed, and the effect of the coexistent gas is canceled to the best possible extent.

Method for correcting the effect of a effect of a coexistent gas in a gas analysis and a gas analyzing apparatus using same

The present invention provides an exhaust gas analyzing system utilizing a mini-diluter method in which measurement accuracy of the exhaust gas analyzing system can be evaluated by the system itself. In the exhaust gas analyzing system, a sampling flow path is connected to an exhaust gas flow path through which gas exhausted from an engine flows to sample a portion of the exhaust gas. The sampled exhaust gas is diluted with dilution gas introduced through a dilution gas flow path which is connected in parallel to the sampling flow path. A portion of the diluted exhaust gas is stored in a sample bag. The diluted exhaust gas in the sample bag is analyzed in a gas analyzing portion, wherein flow rate of the exhaust gas is measured, trace gas with a known concentration is introduced into the exhaust gas flow path upstream from a connecting point located between the exhaust gas flow path and the sampling flow path while monitoring flow rate of the trace gas, diluted trace gas is analyzed in the gas analyzing portion, and total mass of the trace gas calculated from a result of the analysis is compared with total mass of the introduced trace gas to evaluate measurement itself.

Exhaust gas analyzing system

A quantitative analytical method with spectrometric analysis, wherein a sample is irradiated with light, and a plurality of ingredients contained in the sample to be measured are quantitatively determined on the basis of absorptivities at a plurality of appointed wave number points in an absorption spectrum obtained at that time. An assumed concentration-operating matrix is obtained from a combination of reference spectra for a plurality of ingredients, of which the concentrations have been known, and is previously prepared. The concentrations of the respective ingredients to be measured are calculated by the use of the concentration-operating matrix, thereby capable of carrying out a quantitative analysis in a short time with high accuracy.

Quantitative analytical method and apparatus for determining a plurality

A method and apparatus to determine the constituent ingredients in a sample by a spectroscopic procedure is disclosed. A Fourier transformation infrared spectrometer can secure data of a power spectrum of a sample and data of a power spectrum of a reference. A absorption spectrum of the sample from this respective data can be determined. A set of wave number points across the absorption spectrum of the sample that exhibit a predetermined linear characteristic can be selected and the absorption spectrum values corresponding to the set of wave number points can be used to calculate the concentrations of the constituent ingredients. A plurality of sets of wave number points can also be predetermined for a specific sample and limit values can be stored and compared to pick the most desirable set of wave number points for calculating the concentration of the constituent ingredients.

Growing community of inventors

Kyoto, Japan

Kaori Inoue