Abstract: A sensor element includes a porous leading-end protective layer disposed around an outer periphery of an element base in a predetermined range from an end portion on a side where a sensing part is disposed, the protective layer includes: a first layer disposed on two main surfaces of the element base; a second layer disposed to cover the end portion and four side surfaces of the element base including the two main surfaces on which the first layer is disposed; and a layer disposed to cover the second layer, the second layer has a porosity of 30% to 70% and a thickness of 6 to 30 times a thickness of the first layer, and the third layer has a porosity of 10% to 40% and a thickness of 2 to 15 times the thickness of the first layer.

Abstract: A sub adjustment pump cell pumps out oxygen from a measurement gas introduced into a sub adjustment chamber to the extent that H2O and CO2 contained in the measurement gas are not decomposed, a first pump cell pumps out oxygen from a first chamber so that substantially all of H2O and CO2 contained in the measurement gas introduced from the sub adjustment chamber into the first chamber are decomposed, concentrations of H2O and CO2 are identified from a pump-in current when H2 and CO generated by decomposition are oxidized in the second chamber and the third chamber, and a concentration of oxygen contained in the measurement gas is identified based on a magnitude of a current flowing between a sub adjustment inner electrode and an outer electrode at the time when the sub adjustment pump cell pumps out oxygen from the sub adjustment chamber.

Abstract: A gas sensor includes a sensor element and a control unit for controlling the sensor element. The sensor element includes: a base part; a measurement-object gas flow cavity; an oxygen pump cell including an intracavity oxygen pump electrode and an extracavity oxygen pump electrode; a reference gas chamber; and a reference electrode disposed in the reference gas chamber. The control unit includes: a concentration detecting part for detecting an oxygen concentration in a measurement-object gas based on a current value of an oxygen pump current flowing through the oxygen pump cell; and a determining and correcting part for performing correction to the current value of the oxygen pump current flowing through the oxygen pump cell when determining that an oxygen concentration detected by the concentration detecting part is different from an actual oxygen concentration in the measurement-object gas.

Abstract: A gas sensor includes a sensor element and a control device, and configured to measure a water concentration and/or a carbon dioxide concentration in a measurement gas. The control device performs a water concentration measurement processing for measuring the water concentration in the measurement gas based on a second pump current flowing through a second pump cell by a second pump cell control processing, and the sensor element satisfies that a ratio Ih/Ir of a limiting current Ih to a limiting current Ir is 0.44 or less; and/or the control device performs a carbon dioxide concentration measurement processing for measuring the carbon dioxide concentration in the measurement gas based on a third pump current flowing through a third pump cell by a third pump cell control processing, and the sensor element satisfies that a ratio Ic/Ir of a limiting current Ic to the limiting current Ir is 0.24 or less.

Abstract: A gas sensor includes a sensor element and a control unit. The sensor element includes: an oxygen pump cell; a first measurement pump cell; and a second measurement pump cell. The control unit comprises: a pump control part and a concentration calculating part. The pump control part has an oxygen measurement mode and a normal measurement mode; and the concentration calculating part calculates an oxygen concentration in the oxygen measurement mode; calculates a water vapor concentration in the measurement-object gas based on a current flowing through the first measurement pump cell in the normal measurement mode and the oxygen concentration in the oxygen measurement mode; and calculates a carbon dioxide concentration in the measurement-object gas based on a current flowing through the second measurement pump cell in the normal measurement mode and the oxygen concentration in the oxygen measurement mode.

Abstract: A sensor element includes a base part including a plurality of oxygen-ion-conductive solid electrolyte layers stacked; a measurement-object gas flow part for introduction and flow of a measurement-object gas through a gas inlet; an inner oxygen pump electrode disposed on an inner surface of the measurement-object gas flow part; and a measurement electrode disposed on the inner surface of the measurement-object gas flow part. The inner oxygen pump electrode includes: a region (A) including an electrode end close to the gas inlet, and a region (B) including an electrode end far from the gas inlet. A content rate of an activity reducing metal in a metal material in the region (A) is higher than that in the region (B). A ratio of the length of the region (A) of the inner oxygen pump electrode to the length of the inner oxygen pump electrode is 15% to 90%.

Abstract: There are provided high-purity alumina particles in which purity is increased by reducing the amount of impurities remaining in alumina particles derived from metallic aluminum and reducing the amount of metallic aluminum itself and a method of producing the same. The content of elemental uranium in the alumina particles derived from metallic aluminum is 5 ppb or less, the content of elemental thorium is 5 ppb or less, the content of metallic aluminum is 5 ppm or less, the content of sodium is 10 ppm or less, and the content of iron is 10 ppm or less, a metallic aluminum powder is put into a flame, vaporized, and oxidized, and the spherical alumina particles are obtained through spheroidization due to surface tension during cooling, the spherical alumina particles are put into a basic solution to dissolve metallic aluminum remaining in the particles, and the spherical alumina particles are dried.

Abstract: A sensor element includes an element body having formed therein a reference gas chamber in which a reference gas is to be stored; a first pump cell being configured to pump oxygen from around a first pump electrode to around a first reference electrode; a first inner lead portion configured to electrically connect a first connector electrode and the first reference electrode. The first inner lead portion has a reference gas flow region that is porous and constitutes at least part of a reference gas flow path allowing the reference gas to flow between the reference gas chamber and an outside of the element body. A limiting current A when oxygen is pumped out from around the first reference electrode to around the first pump electrode is 1.5 ?A or more.

Abstract: A modified metal oxide particle material includes: a metal oxide particle material having, on a surface thereof, a functional group other than a phenyl group; and a modifying material formed of a silicon-containing compound having a phenyl group. The modifying material is adhered to the surface of the metal oxide particle material. When the modified metal oxide particle material is washed with methyl ethyl ketone, a ratio (C/H) of a carbon content C (% by mass) to a surface area H (m2) per 1 g is 0.05 or less, after the washing. The ratio (C/H) is reduced by 0.1 or more, and the modifying material is removed by 50% or more by mass, after the washing compared with before the washing.

Abstract: A building wall is provided with at least an underlay face member and an overlay face member, the underlay face member directly or indirectly connected to a stud, the overlay face member being an indoor-facing member and connected to the underlay face member, wherein the overlay face member is connected to the underlay face member via at least an adhesive, and wherein a coating amount of the adhesive is less than 100 g/m2.

Abstract: A gas sensor includes: an element body which is internally provided with a measurement-object gas flow portion; a first pump cell including a first inner electrode disposed in the measurement-object gas flow portion; a second pump cell including a second inner electrode disposed in the measurement-object gas flow portion; a heater; a first impedance measurer configured to measure a first impedance by applying a voltage to the first inner electrode; a second impedance measurer configured to measure a second impedance by applying a voltage to the second inner electrode; and a control apparatus configured to perform a heater control process of controlling the heater so that the first impedance reaches a target value, and a correction process of correcting, based on the second impedance, a second pump current which flows through the second pump cell or a value derived based on the second pump current.

Abstract: A gas sensor includes a sensor element and a control device, and configured to measure a concentration of a specific gas in a measurement gas, wherein the control device measures, as the concentration of the specific gas, at least two of a first to fourth concentrations by performing at least two types of the following concentration measurement processing, the at least two types being selected in a combination that uses all of a first to third pump currents: a first concentration measurement processing in which a first concentration is measured; a second concentration measurement processing in which a second concentration is measured; a third concentration measurement processing in which a third concentration is measured; and a fourth concentration measurement processing in which a fourth concentration is measured.

Abstract: A control method of a gas sensor including a sensor element and an activity determining part includes a temperature raising step of heating the sensor element by a heater of the sensor element to raise a temperature of the sensor element up to an active temperature at which the activity determining part determines that the sensor element is in a measurable active state; a prior driving step of raising the temperature of the sensor element by the heater from the active temperature up to a steady driving temperature, and operating a main pump cell and a measurement pump cell of the sensor element to detect NOx in the measurement-object gas; and a steady driving step of maintaining the temperature of the sensor element by the heater at the steady driving temperature, and operating the main pump cell and the measurement pump cell to continuously detect NOx in the measurement-object gas.

Abstract: Provided is a gas sensor element or the like in which a diffusion mode of NOx reaching a measurement electrode is changed from molecular diffusion to a mode of diffusing while repeatedly colliding with a wall face of a sufficiently narrow flow path. In a gas sensor element according to one aspect of the present invention, a porous diffusion layer covering a measurement electrode has a porosity that is lower than the porosity of a leading end protection layer covering at least a face of an element substrate in which a gas inlet is open, and that is 5% or more and 25% or less.

Abstract: A gas sensor includes a sensor element and a control device, and detects a specific gas concentration that is a concentration of a specific gas in a measurement-object gas. The sensor element includes an element body including an oxygen-ion-conductive solid electrolyte layer and provided with a measurement-object gas flow portion therein, the measurement-object gas flow portion introducing the measurement-object gas and causing the measurement-object gas to flow therethrough; a measurement electrode disposed in a measurement chamber of the measurement-object gas flow portion; and a reference electrode disposed inside the element body to come into contact with a reference gas that serves as a reference for detection of the specific gas concentration. The control device measures a voltage across the ground and the reference electrode, and identifies a deviation of the reference potential that is the electrical potential of the reference electrode based on the measured voltage.

Abstract: A gas sensor includes a sensor element and a control unit thereof. The sensor element includes: a base part; a measurement-object gas flow cavity formed from one end part in a longitudinal direction of the base part; a pump cell including an intracavity electrode disposed in the measurement-object gas flow cavity; and a reference electrode disposed in a reference gas chamber formed inside the base part. The control unit includes: a driving control part; a storing part storing in advance, a standard correspondence relationship at a standard time at which a reference potential of the reference electrode is at a predetermined value; and a diagnosing part obtaining a diagnostic correspondence relationship, and comparing the obtained diagnostic correspondence relationship with the standard correspondence relationship to diagnose a deviation of a reference potential of the reference electrode at the diagnostic time from the predetermined value at the standard time.

Abstract: A gas sensor includes a sensor element including an adjustment pump cell and a measurement pump cell, and a control unit including a pump control part. The pump control part performs a startup pump control at a startup of the sensor element, and a steady driving pump control at a steady drive after the startup. In the startup pump control, the pump control part applies, between an inner pump electrode and an outer pump electrode of the adjustment pump cell, a startup voltage of the adjustment pump cell that is higher than a voltage applied in the steady driving pump control; and applies, between an inner measurement electrode and an outer measurement electrode of the measurement pump cell, a startup voltage of the measurement pump cell that is higher than a voltage applied in the steady driving pump control and lower than the startup voltage of the adjustment pump cell.

Abstract: Provided is a gas sensor element or the like in which the diffusion mode of NOx that reaches a measurement electrode is changed from molecular diffusion to a mode of diffusing while repeatedly colliding with a wall face of a sufficiently narrow flow path. In a gas sensor element according to one aspect of the invention, a porous diffusion layer, which accounts for 70% or more of a cross-section of a flow path of a measurement target gas that is orthogonal to a flow direction of the measurement target gas, has a porosity of 5% or more and 25% or less, and is located at a position that is upstream of the measurement electrode and where the distance to the measurement electrode is 0.15 mm or less.

Abstract: A controller of a gas sensor includes: a concentration identification part identifying a concentration of a predetermined gas component based on a measurement pump current flowing between a measurement electrode and an out-of-space pump electrode in accordance with the concentration of the predetermined gas component due to application of a predetermined pump voltage; and a correction processing part correcting the concentration of the predetermined gas component identified by the concentration identification part, the correction processing part corrects the concentration of the predetermined gas component based on a correlation identified in advance between an offset current value as a magnitude of the measurement pump current when a measurement gas not containing the predetermined gas component flows or a normalized value of the offset current value and output fluctuations of the measurement pump current at startup of the gas sensor.

Abstract: An object is to provide a modified metal oxide particle material that maintains high dispersibility even when the amount of modifying material is small. The material includes (i) a metal oxide particle material having, on its surface, a functional group other than a phenyl group; and (ii) a modifying material composed of a silicon-containing compound having a phenyl group, adhered to the surface of the metal oxide particle material. The value C/H, calculated from the carbon content C (mass %) and the specific surface area H (m{circumflex over (?)}2 per g), decreases by ?0.001, ?0.01, or ?0.03 and <0.1 after washing with methyl ethyl ketone. The grind gauge is ?20 ?m. The post-wash C/H is ?0.07.