A method for testing the hydrogen permeability of a test object 1 includes the steps of provision of a sensor device 110 on a first side 3 of the test object 1, application of a test gas 5 including hydrogen 2 to a second side 4 of the test object 1, and detection of permeating hydrogen 2 passing through the test object 1 from the second side 4 to the first side 3 with the sensor device 110, wherein the sensor device 110 includes at least one hydrogen absorbing sensor layer 111 and the detection of the permeating hydrogen 2 including a detection of a change of state of the at least one sensor layer 111. A measuring apparatus 100 for testing the hydrogen permeability of a test object 1 is also described.

The present invention provides a hydrogen sensor having a high sensitivity and low hysteresis characteristics while having a simple configuration and low cost. The present invention shows that a membrane-type surface stress sensor having an amorphous palladium-copper-silicon alloy as a sensitive film has low hysteresis and can detect a nitrogen gas to which hydrogen at a very low concentration of 0.25 ppm is added and a pure nitrogen gas with a sufficiently high S/N ratio.

A gas-detecting apparatus includes a measurement circuit including a gas sensor and a measurement instrument and a decision circuit. Detection cells, included in the gas sensor, each include a first electrode, a second electrode having a surface exposed from an insulation layer, and a metal oxide layer disposed between the first electrode and the second electrode. The resistance values of the detection cells are each allowed to decrease by a contact of gas containing hydrogen atoms with the second electrode. The measurement instrument monitors the resistance values of the detection cells. The decision circuit decides whether the gas is detected or not based on at least one change of the resistance values.

A gas-detecting apparatus includes a gas sensor and a power supply circuit. The gas sensor includes: a first electrode; a second electrode; a metal oxide layer disposed between the first electrode and the second electrode; and an insulation film covering the first electrode, the second electrode, and the metal oxide layer. The insulation file having an opening from which a surface of the second electrode is exposed. The resistance value of the metal oxide layer decreases when gas containing hydrogen atoms comes into contact with the second electrode. The power supply circuit applies a predetermined voltage between the first electrode and the second electrode to increase the resistance value of the metal oxide layer before and/or after the decrease in the resistance value of the metal oxide layer.

A transformer hydrogen gas monitoring system according to an embodiment of the present invention may comprise: a sensor module, which is disposed to allow at least a part thereof to meet hydrogen gas in a transformer and measures a resistance value of a member having a variable resistance value according to a hydrogen concentration in the transformer; and a multi-task module for receiving a sensing result of the sensor module, generating hydrogen concentration information corresponding to resistance value information included in the sensing result, and remotely transmitting information corresponding to the generated hydrogen concentration information.

Disclosed are a hydrogen sensor which includes a P-type silicon nanowire array and a hydrogenation catalyst formed on a surface of the nanowire array, and a method of manufacturing the same.

A gas sensor includes an insulation layer and detection cells covered with the insulation layer. Each of the plurality of detection cells includes: a first electrode; a second electrode having a surface exposed from the insulation layer; and a metal oxide layer disposed between the first electrode and the second electrode. In each of the detection cells, a resistance value of the metal oxide layer decreases with a response time, which is different in each of the detection cells, when a gas containing a hydrogen atom comes into contact with the second electrodes.

Embodiments concern a high-precision, measurement device operative to measure the water content in media and/or water transport rate by media with high precision and with high dynamic range concerning the flow rate value. Based on a molecular transducer principle, captured water reacts with a reactant characterized by its ability to generate gas as a reaction product. By using an electro-chemical transducing element, an electric signal is generated in accordance with a stoichiometric volume of gas produced and water transferred, which is related to the flow rate of the circulating aqueous solution.

The invention relates to a hydrogen sensor (8) and a method for its production, a measuring device (2), and a method for measuring a hydrogen concentration. The hydrogen sensor (8) for measuring a hydrogen concentration in an environment (4) includes a substrate (10) on which a hydrogen-absorbing sensor medium (14) is applied as a thin film in a sensor region (12) communicating with the environment. The sensor medium (14) changes its volume depending on a hydrogen concentration in the sensor medium (14), and said change of the volume causes a variation of a mechanical strain introduced by the sensor medium (14) in the substrate (10). In a preferred embodiment, the substrate (10) of the hydrogen sensor (8) is a piezoresistive semiconductor, at least within the sensor region (12).

A gas sensor (1) including a first gas detection element (2) and a second gas detection element (3), a first storage portion (4) having a first internal space (4A), and a first opening (4B) establishing communication between the first internal space (4A) and the outside space thereof exposed to a detection subject atmosphere, a second storage portion (5) having a second internal space (5A) and a second opening (5B) establishing communication between the second internal space (5A) and the outside space, a first membrane (4C) allowing permeation of water vapor and substantially not allowing permeation of a detection target gas, and covering the first opening (4B), and a calculation unit (12) for calculating the concentration of a detection target gas contained in the detection subject atmosphere, based on outputs from the first and second gas detection elements (2, 3), respectively.