Abstract: A gas detector comprises a gas detection unit and a filter introducing surrounding atmosphere to the gas detection unit. The filter comprises a gas-permeable organic polymer membrane having an acidic group or a basic group.

Abstract: A gas detector comprises a metal oxide semiconductor gas sensor whose resistance decreases in reducing gases and a digital information processing device that treats the output of the gas sensor and compares the output with a comparison value for gas detection. The digital information processing device extracts data representing the resistance of the gas sensor in air from the output of the gas sensor and generates the comparison value such that the larger the resistance of the gas sensor in air is, the larger the ratio between the resistance of the gas sensor in air and a resistance value corresponding to the comparison value is.

Abstract: A gas detector uses a MEMS gas sensor having: a substrate provided with a cavity and an insulating film over the cavity; a metal oxide semiconductor and a heater both provided on the insulating film. A drive circuit operates the heater with a predetermined period for a predetermined pulse duration in order to heat the metal oxide semiconductor. The drive circuit halts operation of the heater or elongates the period when a humidity sensor detects that the atmosphere is humid.

Abstract: A gas sensor comprises a gas separation membrane comprising substituted polyacetylene where a substituent group is combined to a double-bonded carbon atom in the backbone chain of the substituted polyacetylene and a sensing element configured to detect gas permeated through the gas separation membrane.

Abstract: A gas detector uses a MEMS gas sensor having: a substrate provided with a cavity and an insulating film over the cavity; a metal oxide semiconductor and a heater both provided on the insulating film. A drive circuit operates the heater with a predetermined period for a predetermined pulse duration in order to heat the metal oxide semiconductor. The drive circuit halts operation of the heater or elongates the period when a humidity sensor detects that the atmosphere is humid.

Abstract: A micro-hotplate comprises a Si substrate having a cavity and a support layer over the cavity; at least an electrode; and a heater, both provided on the support layer. The electrode surrounds the heater and the heater is disposed inside the electrode. The power efficiency of the micro-hotplate is improved.

Abstract: A gas detector comprises a metal oxide semiconductor gas sensor whose resistance decreases in reducing gases and a digital information processing device that treats the output of the gas sensor and compares the output with a comparison value for gas detection. The digital information processing device extracts data representing the resistance of the gas sensor in air from the output of the gas sensor and generates the comparison value such that the larger the resistance of the gas sensor in air is, the larger the ratio between the resistance of the gas sensor in air and a resistance value corresponding to the comparison value is.

Abstract: A gas detector comprises a gas detection unit and a filter introducing surrounding atmosphere to the gas detection unit. The filter comprises a gas-permeable organic polymer membrane having an acidic group or a basic group.

Abstract: A gas detection unit is accommodated within a housing of a gas sensor and the outside atmosphere of the housing is introduced through the filter to the gas detection unit. The filter comprises an organic polymer gas-permeable filter removing siloxanes and an inorganic filter removing alcohols and passing gases to be detected.

Abstract: An electrochemical gas sensor has a planar ceramic housing having a recess, a MEA, first and second electrically conductive gas diffusion membranes, and a metal lid fixed on the housing so as to cover the recess. The MEA is provided with an ionic conductive membrane, a first electrode on a surface of the membrane, and a second electrode on the opposite surface of the membrane. The first electrically conductive gas diffusion membrane is electrically connected to the first electrical connection. The second electrically conductive gas diffusion membrane is electrically connected to the second electrical connection. The lid presses the second electrically conductive gas diffusion membrane toward the MEA, and in the lid or in the bottom of the housing, a gas inlet is provided. The electrochemical gas sensor is easily made compact, small in the variations in the performances, and easily installed on a print circuit board.

Abstract: An electrochemical gas sensor has a planar ceramic housing having a recess, a MEA, first and second electrically conductive gas diffusion membranes, and a metal lid fixed on the housing so as to cover the recess. The MEA is provided with an ionic conductive membrane, a first electrode on a surface of the membrane, and a second electrode on the opposite surface of the membrane. The first electrically conductive gas diffusion membrane is electrically connected to the first electrical connection. The second electrically conductive gas diffusion membrane is electrically connected to the second electrical connection. The lid presses the second electrically conductive gas diffusion membrane toward the MEA, and in the lid or in the bottom of the housing, a gas inlet is provided. The electrochemical gas sensor is easily made compact, small in the variations in the performances, and easily installed on a print circuit board.

Abstract: It is an object of the present invention to provide a biological information measurement system capable of detecting odiferous gas in defecation gas at sufficient accuracy. The present invention is a system (1) that measures physical condition of a test subject on the basis of a defecation gas, and that includes: a suction device (18); a gas detector (20) with a gas sensor sensitive to an odiferous gas; a control device; a data analyzer (60) that analyzes the physical condition of the test subject; and an output device (68), and a detecting portion of the gas sensor detects gas at an oxidation-reduction temperature at which the detecting portion reacts to the hydrogen gas by an oxidation-reduction reaction, and at an oxidation-reduction reduced temperature at which an oxidation-reduction reaction to the hydrogen gas is deteriorated to relatively raise sensitivity of the detecting portion to the odiferous gas.

Abstract: A gas is detected using a MEMS gas sensor. The electrical power to a heater in the gas sensor is changed between a low level, a high level suitable for detection of detection target gas, and a 0 level, and, therefore, poisonous gas is evaporated or oxidized at the low level, and the detection target gas is detected at the high level.

Abstract: A sensor body of an electrochemical gas sensor having no water reservoir is housed in a metal can including a sensing electrode on one surface of a proton-conducting membrane or a separator retaining an electrolyte and a counter electrode on the opposite surface thereof. The counter electrode is supported by and electrically connected to the metal can via a connecting member. The sensing electrode is connected to a diffusion control plate with the sensing electrode-side ring member, and the ring member is conductive and includes a hole at a center thereof that is connected to a hole of the diffusion control plate.

Abstract: A sensor body of an electrochemical gas sensor having no water reservoir is housed in a metal can including a sensing electrode on one surface of a proton-conducting membrane or a separator retaining an electrolyte and a counter electrode on the opposite surface thereof. The counter electrode is supported by and electrically connected to the metal can via a connecting member. The sensing electrode is connected to a diffusion control plate with the sensing electrode-side ring member, and the ring member is conductive and includes a hole at a center thereof that is connected to a hole of the diffusion control plate.

Abstract: A gas is detected using a MEMS gas sensor. The electrical power to a heater in the gas sensor is changed between a low level, a high level suitable for detection of detection target gas, and a 0 level, and, therefore, poisonous gas is evaporated or oxidized at the low level, and the detection target gas is detected at the high level.