Abstract: Among others, techniques and systems are disclosed for detecting trace levels of heavy metal ions in a sample liquid. A voltage is applied to a sample liquid that includes metal complexes. A current signal associated with the metal complexes is measured. The measured current signal is processed to simultaneously detect a presence of two or more metal ions associated with the metal complexes.

Abstract: The invention relates to a method for the calibration of a device for measuring the total organic carbon content (TOC) of an aqueous solution by measuring resistivity, comprising the following steps, in the presence of a reference TOO analyzer: (a) Producing a calibration point by a measurement carried out on ultrapure water by said device and said analyzer, (b) Producing a plurality of calibration points, each calibration point corresponding to a measurement of the resistivity of a solution having a given content of photo-oxidizable compound, by said device and said analyzer, in order to establish a correlation between the values measured by said device and said analyzer; and (c) Calibrating said device by at least one algorithm, based on the measurements carried out in the previous step.

Abstract: This is a method for analyzing the purity of water at the outlet from a purification device. It comprises the following steps: a) sending the liquid at the outlet from the filter means (1) to a resistivity measuring cell (4) to determine its resistivity PUPW; b) establishing a reference mode by exposing a portion of the liquid to said oxidation means (2) during a given number of significantly different time periods; c) determining by regression the resistivity at infinity p?REF of said liquid in this reference mode; d) establishing an analysis mode by causing said liquid to be analyzed to pass through the resistivity measuring cell (4); e) determining the resistivity at infinity p? of said liquid in this analysis mode by successive iterations; and f) calculating the quantity of organic compounds contained in said purified liquid from this resistivity at infinity p? and at least the values PUPW and P?REF.

Abstract: The invention relates to a method for detecting the presence of boron in water comprising the production of a conductive buffer solution comprising water and at least one boron complexing agent, the introduction into an electrochemical cell of said solution in the presence of at least one work electrode (7), and the measurement of an anodic peak of the boron complex and complexing agent by voltammetry, said method being characterized in that the work electrode (7) is a solid microelectrode, and in that the measurement is carried out continuously with respect to the flow of water. The invention also relates to a device (10) for the implementation of such a method.

Abstract: This is a device for analyzing the quantity of organic compounds existing in a liquid, such as ultrapure water, at the outlet from a purification device including in series filter means (1), oxidation means (2) and polishing means (3), further including means for measuring the resistivity of water to determine the purity thereof, characterized in that it includes only one resistivity measuring cell (4) and in that the outlet points of said filter means (1) and said oxidation means (2) are connected to said resistivity measuring cell (4) by pipes provided with an analysis valve (6) and/or check valves (5) selectively enabling circulation of said liquid within them.

Abstract: The invention relates to a method of measuring the conductivity of a pure or ultrapure liquid, notably water, using electrodes, characterized in that it consists in determining the conductivity by modeling the liquid in the form of an equivalent electrical circuit diagram comprising a resistor R, a capacitor Cp in parallel with the resistor R, and a series capacitor Cs. It also relates to a device for implementing this method and a purification system incorporating such a device.

Abstract: The invention relates to a method of manufacturing a device for measuring conductivity of a liquid, in particular ultrapure water, of the kind comprising two conductivity measurement electrodes suitable for defining a cell constant enabling the measurement of the conductivity of the ultrapure liquid, characterized in that it consists of producing each of the electrodes by forming an electrode pattern from electrically conductive material on a substrate of insulating material. It also relates to the conductivity measuring device obtained by that method and to a device for measuring the Total Organic Carbon quantity implementing that conductivity measuring device.