A chemical sensor includes a sensor element. The sensor element includes a sensitive film and a treatment material. Physical properties of the sensitive film vary as bonding of a target substance to the sensitive film. The sensor element is configured to detect the variation in the physical properties. The treatment material is configured to carry out a treatment onto the target substance before the target substance bonds to the sensitive film. The treatment enhances the variation in the physical properties as compared to a case without the treatment.

A method for estimating a gas concentration of a compound of interest within a process vessel for permitting safe entry into the process vessel comprises: exposing the process vessel to a condensing fluid to dissolve gases therein; collecting liquid comprising the condensing fluid from a location downstream of the process vessel; sealing the liquid in a sample container to yield a condensate sample; measuring and/or calculating properties of a liquid portion and a gas portion of the condensate sample; calculating a process vessel condensate density; determining a thermodynamic equilibrium correction factor; calculating the gas concentration of the compound of interest in the process vessel based on the properties of the condensate sample, a thermodynamic equilibrium correction factor, the process vessel condensate density, and optionally, a safety factor; and determining when the calculated gas concentration of the compound of interest in the process vessel permits safe entry into the process vessel.

A system for detecting an analyte gas in an environment includes a first gas sensor, a first contaminant sensor separate and spaced from the first gas sensor, and electronic circuitry in electrical connection with the first gas sensor to determine if the analyte gas is present based on a response of the first gas sensor. The electronic circuitry is further in electrical connection with the first contaminant sensor to measure a response of the first contaminant sensor over time. The measured response of the first contaminant sensor varies with an amount of one or more contaminants to which the system has been exposed in the environment over time.

A method includes receiving a carrier with a plurality of wafers inside; supplying a purge gas to an inlet of the carrier; extracting an exhaust gas from an outlet of the carrier; and generating a health indicator of the carrier while performing the supplying of the purge gas and the extracting of the exhaust gas.

An apparatus includes: a gas maintenance system having a gas supply system fluidly connected to one or more gas discharge chambers; a detection apparatus fluidly connected to each gas discharge chamber; and a control system connected to the gas maintenance system and the detection apparatus. The detection apparatus includes: a vessel defining a reaction cavity that houses a metal oxide and is fluidly connected to the gas discharge chamber for receiving mixed gas including fluorine from the gas discharge chamber in the reaction cavity, the vessel enabling a reaction between the fluorine of the received mixed gas and the metal oxide to form a new gas mixture including oxygen; and an oxygen sensor fluidly connected to the new gas mixture to sense an amount of oxygen within the new gas mixture. The control system is configured to estimate a concentration of fluorine in the received mixed gas.

An electrochemical cell for sensing gas has added mechanical support for the working electrode to prevent flexure of the working electrode due to pressure differentials. The added mechanical support includes: 1) affixing a larger area of the working electrode to the body of the cell; 2) a gas vent to a cavity of the body to equalize pressures; 3) a rigid electrolyte layer abutting a back surface of the working electrode; 4) infusing an adhesive deep into sides of the porous working electrode to enhance rigidity; 5) supporting opposing surfaces of the working electrode with the rigid package body; and 6) other techniques to make the working electrode more rigid. A bias circuit is also described that uses a controllable current source, an integrator of the varying current, and a feedback circuit for supplying a voltage to the counter electrode and a bias voltage to the reference electrode.

An ultraviolet ray emitter includes an inner tube, an outer tube arranged around the inner tube, the outer tube defining between the outer tube and the inner tube, a discharge space where discharge gas is sealed, a pair of electrodes that causes discharge in the discharge space, and an auxiliary light source that assists excitation of discharge gas by emitting light to discharge gas from the outside of the outer tube. The outer tube is less likely to allow passage therethrough of ultraviolet light generated by excitation of discharge gas than the inner tube but allows passage therethrough of light having a wavelength emitted from the auxiliary light source.

A gas-sensing tattoo sticker includes an adhesive layer, a coloring reaction layer, and a chemical reaction layer, disposed by stacking. The chemical reaction layer includes reaction zones capable of reacting with a gas to be tested to produce a chemical change; the coloring reaction layer includes coloring sides and correspondingly disposed reaction sides in contact with the reaction zones, and includes a coloring indicator to produce a coloring reaction corresponding to the chemical change of the reaction sides; to and the adhesive layer is provided on a side of the coloring reaction layer or the chemical reaction layer to provide adhesion, thereby completing the gas-sensing tattoo sticker, changes of gas in the surrounding environment can be sensed when air inlet sides are outwardly adhered on an object; and the smell of an object itself can be sensed when the air inlet sides are inwardly adhered on the object.

New approaches for selective detection of chemical agents such as sarin are necessary because of the high toxicity of sarin and related compounds, the potential of these compounds to be used as weapons of mass destruction, and the limitations of current detection methodologies. Herein is described an apparatus and a method for selective and amplified detection of sarin simulants deposited via an aerosol process. The simulant absorbs into a hydrogel, where it hydrolyzes upon contact with water producing elemental ions. The elemental ions are then concentrated via an ionic chemical potential gradient to a sensor, where it is detected. This technique has potential to amplify the capture efficiency of a sensor by a 1000-fold within couple of minutes.

A system and method for determining impurities in a beverage grade gas such as CO.sub.2 or N.sub.2 relies on a coupling of FTIR analysis and UV fluorescence detection. Conversion of reduced sulphur present in some impurities to SO.sub.2 can be conducted using a furnace. In some cases, CO.sub.2% also is determined.