A gas detection fuse comprising a thin strip or sheet of a conductive material, such as a metal, connecting two electrodes for detecting a gas of interest. The metal is selected to be reactive with the gas of interest, and has a relatively large surface area, such that when the gas of interest contacts the metal, the electrical connection between the electrodes is broken (e.g., due to the metal losing physical integrity, or becoming non-conductive, as a result of the reaction with the gas). The gas of interest may be chlorine, and the conducting material may be tin. When the tin is exposed to chlorine the tin becomes oxidized to produce liquid tin tetrachloride, thus breaking the electrical connection.

An embodiment provides a method for measuring ozone in a sample, including: introducing at least one alkene to a sample, wherein the alkene in the presence of an amount of ozone produces a carbonyl solution; adding 3-methyl-2-benzothiazolinonehydrazone hydrochloride (MBTH) to the carbonyl solution, and thereafter adding an oxidant to produce at least one imine and oxidized MBTH; producing a conjugated indicator from a reaction of the at least one imine and the oxidized MBTH; and measuring, using a colorimetric technique, an amount of ozone. Other aspects are described and claimed.

Provided are a total organic carbon measurement method and a total organic carbon measurement device capable of determining whether or not an acid has been added to a sample. An acid is introduced into a reaction unit in which the sample is placed from a reservoir in which the acid is reserved (step S103). The conductivity of the sample into which the acid has been introduced is measured (step S105). The introduction of the acid from the reservoir into the reaction unit is detected on the basis of a change in the conductivity of the sample (step S107).

The present invention relates to a direct method for the quantification of sodium in crude oil residues, such as atmospheric residues and vacuum residues by flame atomic absorption spectrometry (FAAS). The proposed method has application in the analysis of sodium in RAT, RV and more frequent oils for monitoring the efficiency of desalting in refineries and the effects of residual salt in other refining processes.

Systems and methods for generating multiple data points for total organic carbon (TOC) analysis of an actively flowing system are disclosed. A TOC device includes a sample fluid passageway and a flow control device, conductivity sensor(s), and an oxidation device located at the sample fluid passageway. A controller operates the flow control device to cause a flow of sample fluid through the sample fluid passageway at a first non-zero flow rate while the oxidation device is active, takes measurement(s) of the sample fluid from the conductivity sensor(s), operates the flow control device to cause a further flow of the sample fluid through the sample fluid passageway at a second non-zero flow rate while the oxidation device is active, and takes further measurement(s) of the sample fluid from the conductivity sensor(s), and generates delta conductivity measurements from the measurements.

For the purpose of providing an analysis method that makes it possible to use, for example, ICP-MS to analyze, with high accuracy, a sample containing mercury, a method for analyzing a sample containing mercury includes: a pretreatment step of adding an oxidizer to a sample containing mercury to prepare a sample solution so as to achieve an oxidation state in which an oxidation-reduction potential is not less than +0.80 V; and an analysis step of subjecting the sample solution which has been prepared in the pretreatment step to a quantitative analysis or a qualitative analysis while maintaining the oxidation state.

A system and a method for determining a concentration of an analyte in a carrier gas of a quasi-binary or binary gas mixture are provided. The system comprise an electrochemical gas sensor. The electrochemical gas sensor comprises a working electrode and a counter electrode. The electrochemical gas sensor is configured by means of the working electrode to oxidize and/or reduce the analyte and to reduce and/or oxidize at least one component of the carrier gas, and to provide a corresponding measurement signal. The system further comprises a memory unit in which calibration information for the gas mixture is stored, and a data processing unit which is configured to: receive the measurement signal, receive the calibration information, determine the concentration of the analyte in the carrier gas from the measurement signal, and, from the calibration information, provide the determined concentration of the analyte in the carrier gas.