A method monitors gases produced in an insulating medium circuit. The insulating medium circuit is in contact with a transition resistor of an on-load tap-changer. The method includes: ascertaining a time profile of a resistor temperature of the transition resistor during a loading time period; and determining at least one characteristic value for characterizing the gases produced based upon the time profile of the resistor temperature.

Ultrasensitive, decoupled thermodynamic sensing platforms for the molecular-level detection of target analytes are disclosed, wherein the sensors have a heating resistor decoupled from a sensing resistor. Embodiments of the decoupled sensor comprise a metallic microheater resistor on one side of substrate, and a sensor resistor coupled to a catalyst on the other side of the substrate. A sensor array may be provided including a plurality of sensors each having a different catalyst that, when exposed to an analyte, each experience an endothermic reaction, an exothermic reaction, or no reaction. A comparison of the reaction results to data comprising previously obtained reaction results may be used to determine the presence and the identity of the analyte. Advantageously, the decoupled sensors utilize less power and provide greater sensitivity than other-known systems, and may be used to detect and identify a single molecule of an analyte.

A combustible gas sensor that includes a reference sensor. The reference sensor includes a first substrate having a first substrate first surface, a first insulating layer disposed on the first substrate first surface, and a first heater at least one of embedded within the first insulating layer and disposed on the first insulating layer. The first substrate is a MEMS substrate.

A combustible gas sensor that includes a reference sensor. The reference sensor includes a first substrate having a first substrate first surface, a first insulating layer disposed on the first substrate first surface, and a first heater at least one of embedded within the first insulating layer and disposed on the first insulating layer. The first substrate is a MEMS substrate.

Described is a calorimeter that includes a thermal column, a sample container, a reference container, a thermal shield, a diffusion-bonded block and a thermal plate. One or more heat flux sensors are disposed between the thermal column and the sample container and between the thermal column and the reference container. The thermal shield is in thermal communication with the thermal column and is separated from and substantially encloses the sample container, reference container and thermal column. The diffusion-bonded block includes a first metallic layer having a first thermal conductivity, a second metallic layer having a second thermal conductivity and a third metallic layer having a third thermal conductivity. The second thermal conductivity is different from the first and third thermal conductivities. The first metallic layer is in thermal communication with the base of the thermal column and the third metallic layer is in thermal communication with the thermal plate.

Described is a calorimeter that includes a thermal column, a sample container, a reference container, a thermal shield, a diffusion-bonded block and a thermal plate. One or more heat flux sensors are disposed between the thermal column and the sample container and between the thermal column and the reference container. The thermal shield is in thermal communication with the thermal column and is separated from and substantially encloses the sample container, reference container and thermal column. The diffusion-bonded block includes a first metallic layer having a first thermal conductivity, a second metallic layer having a second thermal conductivity and a third metallic layer having a third thermal conductivity. The second thermal conductivity is different from the first and third thermal conductivities. The first metallic layer is in thermal communication with the base of the thermal column and the third metallic layer is in thermal communication with the thermal plate.

Described is a calorimeter that includes a thermal column, a sample container, a reference container, a thermal shield, a diffusion-bonded block and a thermal plate. One or more heat flux sensors are disposed between the thermal column and the sample container and between the thermal column and the reference container. The thermal shield is in thermal communication with the thermal column and is separated from and substantially encloses the sample container, reference container and thermal column. The diffusion-bonded block includes a first metallic layer having a first thermal conductivity, a second metallic layer having a second thermal conductivity and a third metallic layer having a third thermal conductivity. The second thermal conductivity is different from the first and third thermal conductivities. The first metallic layer is in thermal communication with the base of the thermal column and the third metallic layer is in thermal communication with the thermal plate.

Described is a calorimeter that includes a thermal column, a sample container, a reference container, a thermal shield, a diffusion-bonded block and a thermal plate. One or more heat flux sensors are disposed between the thermal column and the sample container and between the thermal column and the reference container. The thermal shield is in thermal communication with the thermal column and is separated from and substantially encloses the sample container, reference container and thermal column. The diffusion-bonded block includes a first metallic layer having a first thermal conductivity, a second metallic layer having a second thermal conductivity and a third metallic layer having a third thermal conductivity. The second thermal conductivity is different from the first and third thermal conductivities. The first metallic layer is in thermal communication with the base of the thermal column and the third metallic layer is in thermal communication with the thermal plate.

A system includes a primary combustible gas sensor and a trigger combustible gas sensor including a first trigger element of low-thermal-mass which includes a first trigger heating element in operative connection with electronic circuitry. The trigger combustible gas sensor also includes a second trigger element of low thermal mass including a second trigger heating element. The second trigger element is also in operative connection with the electronic circuitry. The electronic circuitry further has a first trigger mode of operating in which the first trigger element is heated to a temperature at or above a temperature at which the first trigger element causes combustion of the at least one combustible gas analyte and wherein the second trigger element is operated as a trigger compensating element. The electronic circuitry is configured to operate the trigger combustible gas sensor to detect a value of a response at or above a threshold value. The primary combustible gas sensor is activated from a low-power state upon the threshold value being detected by the trigger combustible gas sensor.

A system includes a primary combustible gas sensor and a trigger combustible gas sensor including a first trigger element of low-thermal-mass which includes a first trigger heating element in operative connection with electronic circuitry. The trigger combustible gas sensor also includes a second trigger element of low thermal mass including a second trigger heating element. The second trigger element is also in operative connection with the electronic circuitry. The electronic circuitry further has a first trigger mode of operating in which the first trigger element is heated to a temperature at or above a temperature at which the first trigger element causes combustion of the at least one combustible gas analyte and wherein the second trigger element is operated as a trigger compensating element. The electronic circuitry is configured to operate the trigger combustible gas sensor to detect a value of a response at or above a threshold value. The primary combustible gas sensor is activated from a low-power state upon the threshold value being detected by the trigger combustible gas sensor.