Abstract: A photoionization sensor assembly includes a housing defining a chamber with a first end and an opposing second end and being permeable to the analyte gas and non-analyte gases. A radiation source is structured to emit photons into the chamber. A first, second and third electrode are positioned in the chamber. The photons ionize the analyte gas, are insufficient to ionize the non-analyte gases, and causing ejection of photoelectrons from the third electrode. A controller is structured to receive a measurement of a total pressure and electrically bias the electrodes to collect the photoelectrons on the first and second electrodes in a ratio dependent on the total pressure. The controller is structured to determine the ratio of photoelectrons that are collected on the first and second electrodes at the total pressure and determine an amount of electrical current due to ionization by correcting the measured current using the determined ratio.

Abstract: A gas analyzer and a method for performing mass spectrometry analysis includes a membrane configured to receive an input flow of carrier gas. The membrane defines a variable thickness region between first and second positions along an input face of the membrane and separates the analyte sample into an output flow of analyte molecules. A mass spectrometer is disposed downstream of the membrane and includes an input orifice for receiving the output flow. The mass spectrometer is configured to perform a response profile analysis of the analyte molecules in the sample analyte.

Abstract: A gas analyzer and a method for performing mass spectrometry analysis includes a membrane configured to receive an input flow of carrier gas. The membrane defines a variable thickness region between first and second positions along an input face of the membrane and separates the analyte sample into an output flow of analyte molecules. A mass spectrometer is disposed downstream of the membrane and includes an input orifice for receiving the output flow. The mass spectrometer is configured to perform a response profile analysis of the analyte molecules in the sample analyte.

Abstract: Systems for a managing a chemical process and photoionization detectors for analyzing a process gas are presented. In one aspect, the system includes a process gas source in fluid communication with the process chamber and a photoionization detector. The photoionization detector is configured to analyze the process gas. The photoionization detector includes a heat resistant coupling for connection to the system, a gas sample chamber with the radiation window soldered or brazed to a wall of the gas sample chamber, and a radiation source configured to emit radiation through the radiation window and into the gas sample chamber to analyze the process gas. In another aspect, the photoionization detector includes a removable coupling, a gas sample chamber, and a radiation source. The removable coupling is for connection to the process gas handling system and includes a metal gasket and metal flanges.

Abstract: Systems for a managing a chemical process and photoionization detectors for analyzing a process gas are presented. In one aspect, the system includes a process gas source in fluid communication with the process chamber and a photoionization detector. The photoionization detector is configured to analyze the process gas. The photoionization detector includes a heat resistant coupling for connection to the system, a gas sample chamber with the radiation window soldered or brazed to a wall of the gas sample chamber, and a radiation source configured to emit radiation through the radiation window and into the gas sample chamber to analyze the process gas. In another aspect, the photoionization detector includes a removable coupling, a gas sample chamber, and a radiation source. The removable coupling is for connection to the process gas handling system and includes a metal gasket and metal flanges.

Abstract: A method for forming an ultra-thin membrane for use in a chemical analyzer such as a mass spectrometer includes the step of applying a sacrificial blocking layer onto a porous substrate, applying a semi-permeable membrane layer onto the sacrificial blocking layer, and removing the sacrificial blocking layer following cure of the membrane layer. In a preferred version, at least one of the blocking layer and the membrane layer are applied to the porous support by means of spin coating, though other deposition techniques can be employed.

Abstract: A method for forming an ultra-thin membrane for use in a chemical analyzer such as a mass spectrometer includes the step of applying a sacrificial blocking layer onto a porous substrate, applying a semi-permeable membrane layer onto the sacrificial blocking layer, and removing the sacrificial blocking layer following cure of the membrane layer. In a preferred version, at least one of the blocking layer and the membrane layer are applied to the porous support by means of spin coating, though other deposition techniques can be employed.

Abstract: Chemical sensors for detecting analytes in fluids comprising a plurality of alternating nonconductive regions (comprising a nonconductive material) and conductive regions (comprising a conductive material). In preferred embodiments, the conducting region comprises a nanoparticle. Variability in chemical sensitivity from sensor to sensor is provided by qualitatively or quantitatively varying the composition of the conductive and/or nonconductive regions. An electronic nose for detecting an analyte in a fluid may be constructed by using such arrays in conjunction with an electrical measuring device electrically connected to the conductive elements of each sensor.

Abstract: Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Abstract: Methods, systems and sensor arrays are provided implementing techniques for detecting an analyte in a fluid. The techniques include providing a sensor array including at least a first sensor and a second sensor in an arrangement having a defined fluid flow path, exposing the sensor array to a fluid including an analyte by introducing the fluid along the fluid flow path, measuring a response for the first sensor and the second sensor, and detecting the presence of the analyte in the fluid based on a spatio-temporal difference between the responses for the first and second sensors.

Abstract: Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Abstract: Methods, systems and sensor arrays are provided implementing techniques for detecting an analyte in a fluid. The techniques include providing a sensor array including at least a first sensor and a second sensor in an arrangement having a defined fluid flow path, exposing the sensor array to a fluid including an analyte by introducing the fluid along the fluid flow path, measuring a response for the first sensor and the second sensor, and detecting the presence of the analyte in the fluid based on a spatio-temporal difference between the responses for the first and second sensors.

Abstract: Sensors, sensor arrays and sensing methods provide for detection of a chemical analyte in a fluid. Sensors include a plurality of conductive and nonconductive regions in contact with a measuring apparatus. One or more sensors include a plurality of particles that include a metallic core. Preferably, the particles also include one or more capping ligands coupled to the metallic core. Exposure of the sensors to a fluid containing a chemical analyte causes the analyte to react with the metal core, preferably by displacing one or more of the capping ligands. The chemical analyte can be detected based on a change in electrical or optical properties of the sensors.

Abstract: Methods, systems and sensor arrays are provided implementing techniques for detecting an analyte in a fluid. The techniques include providing a sensor array including at least a first sensor and a second sensor in an arrangement having a defined fluid flow path, exposing the sensor array to a fluid including an analyte by introducing the fluid along the fluid flow path, measuring a response for the first sensor and the second sensor, and detecting the presence of the analyte in the fluid based on a spatio-temporal difference between the responses for the first and second sensors.

Abstract: Sensor arrays and sensor array systems for detecting analytes in fluids. Sensors configured to generate a response upon introduction of a fluid containing one or more analytes can be located on one or more surfaces relative to one or more fluid channels in an array. Fluid channels can take the form of pores or holes in a substrate material. Fluid channels can be formed between one or more substrate plates. Sensor can be fabricated with substantially optimized sensor volumes to generate a response having a substantially maximized signal to noise ratio upon introduction of a fluid containing one or more target analytes. Methods of fabricating and using such sensor arrays and systems are also disclosed.

Abstract: Methods, systems and sensor arrays are provided implementing techniques for detecting an analyte in a fluid. The techniques include providing a sensor array including at least a first sensor and a second sensor in an arrangement having a defined fluid flow path, exposing the sensor array to a fluid including an analyte by introducing the fluid along the fluid flow path, measuring a response for the first sensor and the second sensor, and detecting the presence of the analyte in the fluid based on a spatio-temporal difference between the responses for the first and second sensors.