Abstract: Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ring 1 for the internal combustion engine including a piston ring body 11 having at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film 12, wherein the aluminum cohesion resistance film 12 has a first coating film 12a made of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film 12a.

Abstract: Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ring 1 for the internal combustion engine including a piston ring body 11 having at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film 12, wherein the aluminum cohesion resistance film 12 has a first coating film 12a made of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film 12a.

Abstract: Provided is a piston ring for an internal combustion engine capable of preventing aluminum cohesion for a long time under conditions with high temperature and a high load and also suppressing the wearing of a piston member. A piston ring 1 for the internal combustion engine including a piston ring body 11 having at least one of an upper side face and a lower side face coated with an aluminum cohesion resistance film 12, wherein the aluminum cohesion resistance film 12 has a first coating film 12a made of first ceramics material formed on the piston ring body and a second coating film having Vickers hardness HV smaller than that of the first ceramics material formed on the first coating film 12a.

Abstract: A fuel cell includes: a cell which has a first electrode to be exposed to a first gas, a second electrode to be exposed to a second gas and an electrolyte interposed between the first and second electrodes and which has a first circumferential surface consisting of a curved surface curved in a circular shape and connected to make a full circle; a holding member which has a second circumferential surface consisting of a curved surface curved in a circular shape and connected to make a full circle and opposed to the first circumferential surface over the full circle, and which holds the cell; and an annular seal material which is interposed between the first circumferential surface and the second circumferential surface to separate a channel of the first gas and a channel of the second gas from each other as defined herein.

Abstract: A gas-detecting element comprising an oxygen-ion-conductive solid electrolyte substrate, a sensing electrode fixed onto said solid electrolyte substrate and active with a detection object gas and oxygen, and a reference electrode fixed onto said solid electrolyte substrate and active with at least oxygen, for detecting potential difference between the sensing electrode and the reference electrode to determine the concentration of the detection object gas, the sensing electrode and/or the reference electrode being covered by an electrode-coating layer made of an oxygen-ion-conductive solid electrolyte, and the electrode-coating layer having a portion bonded to the solid electrolyte substrate directly or via an electrode underlayer made of an oxygen-ion-conductive solid electrolyte.

Abstract: The present invention discloses a gas sensing device, an oxygen pumping cell, and a gas detection apparatus using the same for detecting lower ranges of gas concentration with high accuracy and stability. An under layer made of oxygen-ion-conductive solid electrolyte was formed between an electrolyte substrate and a sensing electrode, a conversion electrode or a gas treatment electrode. This allows the physical and chemical adhesion between these electrodes and the electrolyte substrate, thereby improving the sensing properties and stability.

Abstract: A gas-detecting element comprising an oxygen-ion-conductive solid electrolyte substrate, a sensing electrode fixed onto said solid electrolyte substrate and active with a detection object gas and oxygen, and a reference electrode fixed onto said solid electrolyte substrate and active with at least oxygen, for detecting potential difference between the sensing electrode and the reference electrode to determine the concentration of the detection object gas, the sensing electrode and/or the reference electrode being covered by an electrode-coating layer made of an oxygen-ion-conductive solid electrolyte, and the electrode-coating layer having a portion bonded to the solid electrolyte substrate directly or via an electrode underlayer made of an oxygen-ion-conductive solid electrolyte.

Abstract: A gas sensor for measuring concentration of a gas component in a measured gas, including a solid electrolytic substrate and at least two electrodes fixed to the substrate. At least a first electrode of the electrodes is disposed in the environment of the measurement gas, at least one of electrodes is polarized by applying a bias current or bias voltage, and a change in the potential of the polarized electrode is measured to thereby measure the concentration of the target gas.

Abstract: The present invention discloses a gas sensing device, an oxygen pumping cell, and a gas detection apparatus using the same for detecting lower ranges of gas concentration with high accuracy and stability. An under layer made of oxygen-ion-conductive solid electrolyte was formed between an electrolyte substrate and a sensing electrode, a conversion electrode or a gas treatment electrode. This allows the physical and chemical adhesion between these electrodes and the electrolyte substrate, thereby improving the sensing properties and stability.

Abstract: A nitrogen oxide gas sensor wherein an alloy electrode of platinum and rhodium or a cermet electrode of platinum, rhodium, and zirconia or of a rhodium alloy and zirconia is used as the gas sensing electrode. The electrode of the sensor is suitable for measuring nitrogen oxide such as NO and NO2 in an exhaust gas.

Abstract: A nitrogen oxide sensor enabled to enhance the measurement concentration of a total of nitrogen oxides by oxidizing or reducing the nitrogen oxides on the surfaces of electrodes in addition to the control of an oxygen concentration by an oxygen pump. An electrode (3a) in a gas chamber (18) constructing an oxygen pumping portion (3) is made of a material (e.g., Pt-3 wt % Rh) having a function to oxidize a nitrogen oxide gas.

Abstract: A nitrogen oxide sensor includes a solid electrolytic substrate exhibiting oxygen ion conductivity, a noble-metal reference electrode, which is active only to oxygen, formed on one side of the solid electrolytic substrate, and a sensing electrode, which is active to NOx and oxygen, formed on the opposite side of the solid electrolytic substrate. A potential difference across the sensing electrode and the reference electrode is output as a signal indicative of NOx concentration. Nitrogen oxides in a gas to be examined or measured gas are converted to NO2 and to peroxides of nitrogen such as N2O5 and NO3, after which the nitrogen oxides in the gas to be examined or measured gas are sensed by the sensing electrode as the peroxides of nitrogen such as N2O5 and NO3 or as a mixed gas of NO2 and the peroxides of nitrogen.

Abstract: A nitrogen oxide gas sensor wherein an alloy electrode of platinum and rhodium or a cermet electrode of platinum, rhodium, and zirconia or of a rhodium alloy and zirconia is used as the gas sensing electrode. The electrode of the sensor is suitable for measuring nitrogen oxide such as NO and NO2 in an exhaust gas.

Abstract: A nitrogen oxide gas sensor wherein an alloy electrode of platinum and rhodium or a cermet electrode of platinum, rhodium, and zirconia or of a rhodium alloy and zirconia is used as the gas sensing electrode. The electrode of the sensor is suitable for measuring nitrogen oxide such as NO and NO2 in an exhaust gas.

Abstract: A stable sensor designed to detect accurately the total NOx concentration under 100 ppm in terms of the NO gas concentration is made up of a first cell and a second cell with a gas diffusion aperture provided between the two cells. The first cell has a partition wall of a substrate of oxygen ion conductor containing zirconia as the main component and permitting a gas to be detected to enter the zirconia substrate; oxygen pumping electrodes are also formed on the first cell substrate which functions to expel oxygen in an atmosphere of the first cell to the outside and to reduce NO.sub.2 of the NOx gas to be detected to NO gas.