In various embodiments, both very high speed and very high sensitivity hydrogen detection is achieved by controlling water vapor concentration over the catalyst used to convert hydrogen in sample gas (e.g., ambient air) to water vapor, to provide a substantially stable water vapor mixing level at a target mixing ratio. The naturally-occurring water vapor in the sample gas, without further steps, typically would vary over time within a wide range (e.g., due to changing atmospheric conditions). By controlling a level of water vapor over the catalyst to be substantially equal to a target mixing ratio that is not too low as to impair response time, and not too high as to impair sensitivity, both very high speed and very high sensitivity can be provided.

The present invention brings an actual concentration of a process gas closer to an ideal concentration, and a gas analysis device that is used in a fluid control system that controls a process gas obtained by vaporizing a liquid material or a solid material, the gas analysis device including: a first concentration calculation unit that calculates a concentration of the process gas; a second concentration calculation unit that calculates a concentration of a by-product gas at least generated in a side reaction that is a reaction different from a main reaction for generating the process gas; a comparison unit that compares a first actual concentration that is the concentration of the process gas calculated by the first concentration calculation unit with a first ideal concentration, and compares a second actual concentration that is the concentration of the by-product gas calculated by the second concentration calculation unit with a second ideal concentration.

An apparatus for quantitatively analyzing gas, particularly oxygen, generated in a battery material, particularly a cathode material is provided. The apparatus contains a switching valve and a sampling loop in a pyrolyzer, thereby allowing an EGA method, which was used only for the qualitative analysis of gas generated from a solid sample, to be used for the quantitative analysis of gas generated at a specific temperature when heat is applied by the pyrolyzer in a battery material.

An OH radical detection probe (102) includes an aromatic carboxylic acid, a polar aprotic organic solvent, and a polar protic organic solvent.

An apparatus for quantitatively analyzing gas, particularly oxygen, generated in a battery material, particularly a cathode material is provided. The apparatus contains a switching valve and a sampling loop in a pyrolyzer, thereby allowing an EGA method, which was used only for the qualitative analysis of gas generated from a solid sample, to be used for the quantitative analysis of gas generated at a specific temperature when heat is applied by the pyrolyzer in a battery material.

The present invention relates to a gas detector cell unit comprising a gas cell, the unit comprising an outer housing providing access to the gas outside through a protecting filter adapted to making gas cell safe for use in explosive environments, i.e. a sintered filter, and the unit comprising means for detecting reduction in the circulation through said protecting filter.

A combustion analyzer system includes an analyzer unit, a primary analysis probe and one or more remote probes. The analyzer unit includes a condensation removal unit and two or more electrochemical sensors to detect at least oxygen and carbon monoxide. The analyzer unit also includes a means for sealing or isolating the electrochemical sensor inputs to prevent oxidation of the reactive elements when the unit is not in use.

Gas analyzer and method for measuring nitrogen oxides in an exhaust gas, wherein to measure the nitrogen oxides, ozone is generated from oxygen, the exhaust gas is treated with the ozone generated to convert nitrogen monoxide within the exhaust gas into nitrogen dioxide, the nitrogen dioxide concentration in the treated exhaust gas is measured photometrically using a first light-emitting diode which emits with a central wavelength between 350 nm and 500 nm and output as the nitrogen oxide concentration in the exhaust gas, and the ozone concentration in the treated exhaust gas is measured photometrically using a second light-emitting diode which emits with a central wavelength between 250 nm and 265 nm, where generation of the ozone using the measured ozone concentration as an actual value is regulated to a prespecified setpoint value to enable reliable continuous measurement of nitrogen oxides in exhaust gases with a low outlay on equipment.

A gas sensor and the drive circuit for the sensor are installed within a mobile electronic device. The gas sensor is intermittently heated to an operating temperature for detecting gases and kept at an ambient temperature for other periods. When a sensor of the mobile electronic device detects that the device is placed in a closed space, the heating of the metal oxide semiconductor is halted. When the sensor detects that the mobile electronic device has been taken out from the closed space, the heating of the metal oxide semiconductor is resumed. The poisoning of the gas sensor by siloxanes or the like is prevented.

The present invention relates to a gas detector cell and cell unit for optical detection of a predetermined gas, the cell being provided with optical means for investigating a gas sample present in the cell. The cell is constituted by a volume enclosed in a container, at least part of the container wall being constituted by a membrane, the membrane being provided with openings allowing diffusion of gas therethrough, and the membrane openings being provided with a catalyst for converting the gas diffusing therethrough to said predetermined gas.