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.

Embodiments of the present disclosure relate to a preparation and feed apparatus of a standard sample for calibration of a trace-analysis instrument, and especially to a preparation and feed apparatus of a standard sample for calibration of a gas chromatograph-ion mobility spectrometer. When the trace-analysis instrument is being calibrated by taking advantage of the preparation and feed apparatus according to embodiments of the disclosure, it is unnecessary to use an additional dedicated tool and steps to prepare the sample for testing and to use an organic solvent or a dedicated sample application/dispensing tool, resulting in that the trace-analysis instrument is simple and convenient to carry and use, and the substance for calibration is also convenient to store and exchange; moreover, the trace-analysis instrument is also safe, reliable and environmentally friendly.

The present invention is one that accurately measures an exhaust gas component regardless of variation in atmospheric pressure around a test object that is a vehicle or part of it, and an exhaust gas analysis apparatus that measures component concentration in exhaust gas discharged from the test object that is the vehicle or part of it. The exhaust gas analysis apparatus includes: an exhaust gas detector that mixes the exhaust gas and reactive gas together and detects the resulting phenomenon; a pressure gauge that measures the atmospheric pressure at the time of measurement of the exhaust gas or pressure at a predetermined point inside the exhaust gas analysis apparatus as measured pressure; and a correction part that, on the basis of the measured pressure by the pressure gauge, corrects the measurement error of the exhaust gas detector associated with a variation in the supply amount of the reactive gas.

The present invention relates to a method (1) for determining a content of H.sub.2S in a process gas comprising H.sub.2S. The method (1) comprises extracting (2) a sample of the process gas, performing oxidation (4) of at least a major portion of H.sub.2S of the sample, whereby oxidation products comprising elemental sulfur are formed, analysing (6) the oxidized sample by optical absorption spectroscopy at wavelengths above 310 nm, and determining (8) the content of H.sub.2S in the process gas based on the analysing. The invention further relates to a system (100) for determining a content of H.sub.2S in a process gas comprising H.sub.2S, and use of system (100).

An elemental analysis system includes a reactor having at least one reduction reaction zone including a metal zeolite that can reduce nitrogen oxides (NO.sub.x) to molecular nitrogen (N.sub.2) by selective catalytic reduction. Correspondingly, a method of elemental analysis includes providing a reactor having at least one reduction reaction zone including a metal zeolite and reducing nitrogen oxides (NO.sub.x) to molecular nitrogen (N.sub.2) by selective catalytic reaction on the metal zeolite.

A core-shell structure (a diameter is about 5 nm) is located on an Al.sub.2O.sub.3 catalyst support. Platinum (Pt metal) is a core, and a shell that surrounds the core has a solid solution structure (A.sub.1-xB.sub.xO.sub.Y) (where X is a composition that composes A and B, and Y is a composition of oxygen (O)) that is composed of platinum, palladium, and oxygen.

Apparatus comprising an inlet region for receiving a gas mixture; an ionizer for supplying hydronium ions to the received gas mixture to generate ions, wherein the ionizer comprises a membrane for receiving the gas mixture, and wherein the membrane, preferably made of graphene oxide, is capable of generating hydronium ions from water; and an ion detector for detecting ions generated from the gas mixture.

The present disclosure is directed to a selective multi-gas sensor device that detects when a high concentration level of a particular gas, such as methane, carbon monoxide, and/or ethanol, is present. The selective multi-gas sensor device detects and identifies a particular gas based on a ratio between a sensitivity of a gas sensitive material at a first temperature and a sensitivity of the gas sensitive material at a second temperature.

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.

A method for the detection of polycyclic aromatic hydrocarbons including: a) a step of contacting an aqueous solution including at least one polycyclic aromatic hydrocarbon with a catalyst for the oxidation of polycyclic aromatic hydrocarbons and with an electrode made of a conductive porous material, and b) a step of detecting the anthraquinone that is formed during the previous step through the oxidation of the polycyclic aromatic hydrocarbons.