A microhotplate comprising a membrane suspended over a substrate by a plurality of tethers connected between the substrate and the membrane. The membrane comprises a resistive heater comprising an electrically conductive material having a varying width from a peripheral portion of the membrane to a center of the membrane. The electrically conductive material comprises a first portion spiraling in a first direction and a second portion spiraling in a second direction and in electrical communication with the first portion at the center of the membrane. The microhotplate further comprises a first electrically conductive trace extending over a first tether and in electrical contact with a bond pad on the substrate and the first portion and a second electrically conductive trace extending over another tether and in electrical contact with another bond pad on the substrate and the second portion. Related chemical sensors and related methods of detecting at least one analyte are also disclosed.

A microhotplate comprising a membrane suspended over a substrate by a plurality of tethers connected between the substrate and the membrane. The membrane comprises a resistive heater comprising an electrically conductive material having a varying width from a peripheral portion of the membrane to a center of the membrane. The electrically conductive material comprises a first portion spiraling in a first direction and a second portion spiraling in a second direction and in electrical communication with the first portion at the center of the membrane. The microhotplate further comprises a first electrically conductive trace extending over a first tether and in electrical contact with a bond pad on the substrate and the first portion and a second electrically conductive trace extending over another tether and in electrical contact with another bond pad on the substrate and the second portion. Related chemical sensors and related methods of detecting at least one analyte are also disclosed.

A microhotplate comprising a membrane suspended over a substrate by a plurality of tethers connected between the substrate and the membrane. The membrane comprises a resistive heater comprising an electrically conductive material having a varying width from a peripheral portion of the membrane to a center of the membrane. The electrically conductive material comprises a first portion spiraling in a first direction and a second portion spiraling in a second direction and in electrical communication with the first portion at the center of the membrane. The microhotplate further comprises a first electrically conductive trace extending over a first tether and in electrical contact with a bond pad on the substrate and the first portion and a second electrically conductive trace extending over another tether and in electrical contact with another bond pad on the substrate and the second portion. Related chemical sensors and related methods of detecting at least one analyte are also disclosed.

A microhotplate comprising a membrane suspended over a substrate by a plurality of tethers connected between the substrate and the membrane. The membrane comprises a resistive heater comprising an electrically conductive material having a varying width from a peripheral portion of the membrane to a center of the membrane. The electrically conductive material comprises a first portion spiraling in a first direction and a second portion spiraling in a second direction and in electrical communication with the first portion at the center of the membrane. The microhotplate further comprises a first electrically conductive trace extending over a first tether and in electrical contact with a bond pad on the substrate and the first portion and a second electrically conductive trace extending over another tether and in electrical contact with another bond pad on the substrate and the second portion. Related chemical sensors and related methods of detecting at least one analyte are also disclosed.

A differential thermal analysis of a plurality of metal-resin-containing layers, the resin material amounts of which are known and different from each other, is carried out. Heights of sample peaks observed at one temperature in the differential thermal analysis are measured, and a correlation between the resin material amounts and the sample peak heights is obtained. Then, a differential thermal analysis of a porous metal body is carried out, and a height of a peak observed at the same temperature is measured. An amount of a residual resin material in the porous metal body is obtained based on the measured height and the correlation.

A differential thermal analysis of a plurality of metal-resin-containing layers, the resin material amounts of which are known and different from each other, is carried out. Heights of sample peaks observed at one temperature in the differential thermal analysis are measured, and a correlation between the resin material amounts and the sample peak heights is obtained. Then, a differential thermal analysis of a porous metal body is carried out, and a height of a peak observed at the same temperature is measured. An amount of a residual resin material in the porous metal body is obtained based on the measured height and the correlation.

Disclosed is a gas sensor. The gas sensor comprises: a substrate; a thermoelectric layer which is disposed on the substrate and has a metal nanowire; a first electrode and a second electrode disposed to be spaced apart from each other on the thermoelectric layer; and a catalyst layer which is disposed on the first electrode and has a composite structure in which a metal particle is bonded to a carbon structure.

Disclosed is a gas sensor. The gas sensor comprises: a substrate; a thermoelectric layer which is disposed on the substrate and has a metal nanowire; a first electrode and a second electrode disposed to be spaced apart from each other on the thermoelectric layer; and a catalyst layer which is disposed on the first electrode and has a composite structure in which a metal particle is bonded to a carbon structure.

An information processing method is performed by a computer for evaluating flammability of a mixed refrigerant material containing a plurality of components. The method includes: calculating, for each of the plurality of components, a second value obtained by multiplying a mixture ratio thereof in the mixed refrigerant material by a first value obtained based on numbers of hydrogen atoms, halogen atoms, and double bonds included in a molecular structure thereof; calculating a total sum of the second value calculated for each of the plurality of components; and classifying the mixed refrigerant material into a predetermined flammability class based on the total sum.

An information processing method is performed by a computer for evaluating flammability of a mixed refrigerant material containing a plurality of components. The method includes: calculating, for each of the plurality of components, a second value obtained by multiplying a mixture ratio thereof in the mixed refrigerant material by a first value obtained based on numbers of hydrogen atoms, halogen atoms, and double bonds included in a molecular structure thereof; calculating a total sum of the second value calculated for each of the plurality of components; and classifying the mixed refrigerant material into a predetermined flammability class based on the total sum.