The disclosure relates to a wireless self-powered gas sensor based on electromagnetic oscillations triggered by external forces and its fabrication method. The sensor includes a gas test chamber, a first friction layer, a second friction layer, an interdigital electrode, a gas-sensitive material, an air inlet, an air outlet and leads. The gas sensor of the disclosure is an integrated detection system of “environmental energy collection—wireless energy transmission—active spontaneous detection” that can be driven simultaneously only by external mechanical movement, and can work independently without external power supply. The first friction layer and the second friction layer are arranged outside the gas test chamber. The frictional motion will not interfere with the flow field of the test chamber and the gas molecule absorption and desorption, which ensures the stability of gas detection to the greatest extent.

A sensor includes a first sensing element electronically sensitive to an analyte and to an interfering stimulus. The first sensing element provides a first electrical signal in response to a presence of the analyte and/or the interfering stimulus. The sensor also includes a second sensing element electronically sensitive to the analyte and to the interfering stimulus. The second sensing element provides a second electrical signal in response to the presence of the analyte and/or the interfering stimulus. A conductive link electrically connects the first sensing mechanism and the second sensing mechanism. An electrical property is measured within the sensor that is indicative of a concentration of the analyte based on the first electrical signal and the second electrical signal.

Environmental conditions affecting a sensor having a thermal coefficient are compensated by applying an adaptive filter to an environmental condition reference signal. The resulting adaptive cancellation signal may be used to provide feedback control to a first heating element.

Systems, devices, and methods are described herein for a vapor or gas sampling device. In one aspect, the described collector may include an outer tube having first and second ends, with the hollow tube forming a plurality of perforations proximate to the first end. In some examples, the perforations may prevent the passing of detritus or environmental contaminants through the perforations. The collector may also include inner tube having a first end and a second end, with the hollow tube forming a plurality of perforations proximate to the second end, which is opposite the first end of the outer tube. The inner tube may be positioned or affixed at least partially inside of the outer tube. The perforations on the inner tube may be located towards the second end when relative to the perforations on the outer tube, such that the perforations of the two tubes do not overlap.

Various example embodiments described herein relate to a sensor assembly. The sensor assembly includes a first sensor cover and a second sensor cover. The first sensor cover is disposed on a first end of the sensor assembly and the second sensor cover is disposed on a second end of the sensor assembly. The first sensor cover defines a first capillary and the second sensor cover defines a second capillary therethrough. The sensor assembly further includes a first sensing unit, a second sensing unit, and a filter. The first sensing unit and the second sensing unit are disposed between the first sensor cover and the second sensor cover. In some example embodiments, the filter is reactive to a target gas and thereby prevents an inflow of the target gas through the second capillary into the sensor assembly.

Improved optical absorption spectroscopy of species having broad spectral features is provided by choosing frequencies to cover the spectral feature(s) of interest, where the frequencies are slightly adjusted as needed to avoid narrow spectral features from interfering chemical species (i.e., clutter). The resulting clutter avoidance provides improved optical spectroscopy of species having broad spectral features.

A sensor includes a first sensing element electronically sensitive to an analyte and to an interfering stimulus. The first sensing element provides a first electrical signal in response to a presence of the analyte and/or the interfering stimulus. The sensor also includes a second sensing element electronically sensitive to the analyte and to the interfering stimulus. The second sensing element provides a second electrical signal in response to the presence of the analyte and/or the interfering stimulus. A conductive link electrically connects the first sensing mechanism and the second sensing mechanism. An electrical property is measured within the sensor that is indicative of a concentration of the analyte based on the first electrical signal and the second electrical signal.

A gas detection unit is accommodated within a housing of a gas sensor and the outside atmosphere of the housing is introduced through the filter to the gas detection unit. The filter comprises an organic polymer gas-permeable filter removing siloxanes and an inorganic filter removing alcohols and passing gases to be detected.

Systems, devices, and methods are described herein for an auxiliary heat exchange system for use in scientific sampling. In one aspect, a heat exchange system may include at least one first conduit housed in an external casing, that is removably attachable to a heat/cooling system of a vehicle. Another conduit, such as a tracer tube, may be positioned proximate to the first conduit and housed in the external casing for at least a partial length of the first conduit. The tracer conduit may include a first end that is removably attachable to a gas collection device and a second end removably attachable to a measuring device. The first conduit may be configured to carry heated liquid from the heating/cooling system of the vehicle to maintain at least a threshold temperature of gas samples in the tracer conduit to prevent or reduce the formation of condensates in the tracer conduit.

The disclosure relates to a wireless self-powered gas sensor based on electromagnetic oscillations triggered by external forces and its fabrication method. The sensor includes a gas test chamber, a first friction layer, a second friction layer, an interdigital electrode, a gas-sensitive material, an air inlet, an air outlet and leads. The gas sensor of the disclosure is an integrated detection system of environmental energy collectionwireless energy transmissionactive spontaneous detection that can be driven simultaneously only by external mechanical movement, and can work independently without external power supply. The first friction layer and the second friction layer are arranged outside the gas test chamber. The frictional motion will not interfere with the flow field of the test chamber and the gas molecule absorption and desorption, which ensures the stability of gas detection to the greatest extent.