Otsuka Pharmaceutical Company, Limited

Otsuka Electronics Co., Ltd.

Yasuhiro Kubo

Masaaki Mori

Kazunori Tsutsui

Tamotsu Hamao

Yasushi Zasu

Koichi Oka

Katsuhiro Morisawa

Eiji Ikegami

Takashi Maruyama

Akira Kawaguchi

Motonobu Akagi

Kunio Kumagai

Masayuki Tani

Masahiko Miyoshi

Hiroaki Mizui

William Otani

An exhalation collected in a breath bag capable of expanding and contracting is sucked into a gas inlet vesselwith a given volume (Va), and then the gas inlet vesselis communicated by means of valve Vwith a cellthat is maintained at an atmospheric pressure by being pre-filled with a sample gas or reference gas. After the communication, the gas pressure is measured by a pressure sensorattached to the cell. Whether the exhalation collected in the breath bag is below a given amount or not can be accurately judged.

Method of exhaled gas measurement and analysis and apparatus therefor

As previous processing of measurement in which gas to be measured containing, as gas components, carbon dioxideCOand carbon dioxideCO, is introduced into a cell, and in which the intensities of transmitted lights having wavelengths suitable for measurement of the respective gas components, are measured and then data-processed to measure the concentrations of the gas components, the air having a predetermined volume Va is sucked by a gas injection device, a gas exhaust valve Vof a cellis closed and the air stored in the gas injection deviceis transferred to the cellfilled with the air at an atmospheric pressure, thereby to pressurize the cell inside. The pressure thus pressurized is measured as P. The cell volume Vc is subtracted from the product obtained by multiplying the sum. Vof the volume Va and Vc the cell volume Vc, by the ratio P/P in which Pis the target pressure of the gas to be measured at which a calibration curve has been prepared for an isotope gas analysis and measurement, thus determining the one-time gas injection amount of the gas injection device. Thus, measured concentration variations based on changes in atmospheric pressure can be corrected.

Gas injection amount determining method in isotope gas analysis, and isotope gas analyzing and measuring method and apparatus

In an isotopic gas analyzer, a gas injector () is provided for pressurizing a gas specimen in cells (). The pressurization of the gas specimen virtually produces the same effect as increasing the concentration of carbon dioxide in the gas specimen, thereby improving an S/N ratio for the analysis and hence data reproducibility.

Isotopic gas analyzer and method of judging absorption capacity of carbon dioxide absorbent

A test gas sample containing carbon dioxide CO as a component gas is introduced into a cell, then the absorbance of light transmitted therethrough at a wavelength suitable for the component gas CO is determined, and the concentration of the component gas is determined on the basis of a calibration curve prepared through measurement on test gas samples each containing the component gas in a known concentration. Further, the concentration of water vapor contained in the test gas sample is measured, and the concentration of the component gas in the test gas sample is corrected in accordance with the measured water vapor concentration on the basis of a correction curve prepared through measurement on the test gas samples each containing water vapor in a known concentration (FIG. 4). With the spectrometry, the concentration ratio of the component gas can precisely be determined and corrected by measuring the moisture content in the test gas sample.

Stable isotope measurement method and apparatus by spectroscopy

A test gas sample containing carbon dioxide CO as a component gas is introduced into a cell, then the absorbance of light transmitted therethrough at a wavelength suitable for the component gas CO is determined, and the concentration of the component gas is determined on the basis of a calibration curve prepared through measurement on test gas samples each containing the component gas in a known concentration. Further, the concentration of water vapor contained in the test gas sample is measured, and the concentration of the component gas in the test gas sample is corrected in accordance with the measured water vapor concentration on the basis of a correction curve prepared through measurement on the test gas samples each containing water vapor in a known concentration (FIG. ). With the spectrometry, the concentration ratio of the component gas can precisely be determined and corrected by measuring the moisture content in the test gas sample.

A correction curve (FIG.,) is prepared by plotting,CO,concentrations and,CO,/,CO,concentration ratios which are determined on the basis of a calibration curve and,CO,and,CO,absorbances of gaseous samples having the same,CO,/,CO,concentration ratio but known different,CO,concentrations. A gaseous test sample containing,CO,and,CO,as component gases is introduced into a cell, and spectrometrically measured. A,CO,concentration of the gaseous test sample is determined by way of the spectrometric measurement. A concentration ratio correction value is obtained on the basis of the correction curve and the,CO,concentration of the gaseous test sample thus determined. A measured,CO,/,CO,concentration ratio is divided by the concentration ratio correction value thus obtained for correction of the,CO,/,CO,concentration ratio. Thus, the measurement accuracy of the concentration ratios of the component gases can be improved.

Method for spectrometrically measuring isotopic gas and apparatus thereof

Apparatus and breathing bag for spectrometrically measuring isotopic gas

A differential refractometer in which: light from a light source is condensed on a lens; the light thus condensed is guided to a cell which houses a sample of which refractive index is to be measured and a reference of which refractive index is used as a reference value, the sample and the reference being housed as separated from each other in the cell; the light having passed through the cell is guided to an image sensor; and the amount of light deflection due to the difference in refractive index between the sample and the reference is measured, thereby to obtain the refractive index of the sample. The differential refractometer comprises: a light permeable member disposed at such a position that the light permeable member and the image sensor are optically conjugate with respect to the lens, the light permeable member carrying an image having at least two identification portions; and a spatial filter disposed between the light permeable member and the image sensor and adapted to spatially filter light portions which have passed through the two identification portions, the spatial filter causing at least one of the light portions thus spatially filtered to pass through the cell. The refractive index of the sample may be obtained based on the distance between the positions of images, on the detecting surface of the image sensor, of the two identification portions of the light permeable member. Such an arrangement may improve the measuring precision and reduce the number of component elements.

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Konan, Japan

Yasuhiro Kubo