The described semiconductor device can include a two-transistor pixel array. Each pixel in the two-transistor pixel array can include a chemical detection pixel comprising a chemically-sensitive transistor and a row-selection transistor connected between a current source and a chemically-sensitive transistor. The source of the chemically-sensitive transistor can be coupled to a column line, and the drain of the chemically-sensitive transistor can be coupled to the source of the row selection transistor. The gate of the row selection transistor can be couple to a row line. When a row line is activated, the row selection transistor can couple the chemically-sensitive transistor to the column line.

The described embodiments may provide a chemical detection circuit that may comprise a plurality of first output circuits at a first side and a plurality of second output circuits at a second side of the chemical detection circuit. The chemical detection circuit may further comprise a plurality of tiles of pixels each placed between respective pairs of first and second output circuits. Each tile may include four quadrants of pixels. Each quadrant may have columns with designated first columns interleaved with second columns. Each first column may be coupled to a respective first output circuit in first and second quadrants, and to a respective second output circuit in third and fourth quadrants. Each second column may be coupled to a respective second output circuit in first and second quadrants, and to a respective first output circuit in third and fourth quadrants.

A method for preparing a sample for analysis includes separating a gas sample into at least one component sample in a separation unit. The output of the at least one component sample from the separation unit is detected, for example, using a thermal conductivity detector. A hydrocarbon in the component sample is combusted in a combustion unit to generate a combustion product. The at least one component sample is collected in a sample collector and supplied to an analysis unit. In some embodiments, the analysis unit may be used to determine an isotopic ratio of the at least one component sample.

A method and device to adjust the concentration of at least two gasses in a fluid, wherein the method involves adjusting the concentration of a first gas in the fluid by adjusting the concentration of a second gas in the fluid wherein the first and second gases are kept separate until dissolved in the fluid.

A device (201) is provided for collecting a substance from an ambient fluid. The device includes a housing (205) equipped with an (207) inlet and an outlet (209) which are in fluidic communication with each other, and a collector (203) which has a plurality of spaced-apart layers (213). The collector is disposed in a fluidic flow path between the inlet and the outlet such that a flow of fluid passes through adjacent layers of the collector. Each of the layers includes a substrate (217) having a sorbent or adherent (219) disposed thereon, and a plurality of embossments (215) which maintains the layers in the spaced-apart configuration.

A reaction carrier (14), a measuring device (12) and a measuring method measure a concentration of gaseous/aerosol components of a gas mixture. The reaction carrier (14) has a flow channel (42) defining a reaction chamber (46) with an optically detectable reaction material (48) reacts with at least one component of the gas mixture or with a reaction product of the component. A humidity measuring element (84), of the reaction carrier (14), detects a humidity of the gas mixture flowing through the flow channel (42). The measuring device (12) has a humidity detection unit (85) that reads the humidity measuring element (84). A humidity determining unit (94) determines a humidity based on the detected humidity. The measuring method determines a humidity of the supplied gas mixture in the flow channel (42) and determines a concentration of the component on the basis of the optically detectable reaction and the measured humidity.

A method and system are provided for detecting the concentration of an analyte in a fluid sample. The method and system involve analysis of a volatilized, ionized fluid sample using a mass spectrometer or other ionic analyte detection device that provides a signal proportional in intensity to the quantity of ionized analyte detected. The improvement involves replacement of a necessary non-analyte component in the fluid sample with a substitute component that serves the same purpose as the original component but is either more volatile than the original component and/or the analyte or undergoes a reaction to provide lower molecular weight reaction products, and results in an increased intensity in signal and signal-to-noise ratio. Acoustic fluid ejection is a preferred method of generating nanoliter-sized droplets of fluid sample that are then volatilized, ionized, and analyzed. Also provided are zwitterionic compounds suitable as the substitute components that when ionized and heated decompose to provide carbonic dioxide, a nitrogenous species such as ammonia, an amine, or nitrogen gas, and a volatile aromatic compound.

The described embodiments may provide a chemical detection circuit that may comprise a plurality of first output circuits at a first side and a plurality of second output circuits at a second side of the chemical detection circuit. The chemical detection circuit may further comprise a plurality of tiles of pixels each placed between respective pairs of first and second output circuits. Each tile may include four quadrants of pixels. Each quadrant may have columns with designated first columns interleaved with second columns. Each first column may be coupled to a respective first output circuit in first and second quadrants, and to a respective second output circuit in third and fourth quadrants. Each second column may be coupled to a respective second output circuit in first and second quadrants, and to a respective first output circuit in third and fourth quadrants.

A device (201) is provided for collecting a substance from an ambient fluid. The device includes a housing (205) equipped with an (207) inlet and an outlet (209) which are in fluidic communication with each other, and a collector (203) which has a plurality of spaced-apart layers (213). The collector is disposed in a fluidic flow path between the inlet and the outlet such that a flow of fluid passes through adjacent layers of the collector. Each of the layers includes a substrate (217) having a sorbent or adherent (219) disposed thereon, and a plurality of embossments (215) which maintains the layers in the spaced-apart configuration.

In a measuring method for measuring an atmospheric concentration of a compound, such as a volatile organic compound (VOC), an adsorptive element is provided within a target atmosphere for a period of time to allow adsorption of a compound of interest, and then removed from the target atmosphere, and placed within a closed measuring space. The adsorptive element is heated within the measuring space to cause de-adsorption of the compound into the closed measuring space, and a concentration of the de-adsorbed compound is measured. A concentration of the compound in the target atmosphere is determined based on the concentration of the compound within the closed measuring space. The adsorptive element may be formed of an adsorptive material such as carbon fibers, cellulose or other adsorptive materials, and a binder. The adsorptive element may be optimized for adsorption of a specific compound.