Abstract: A transport container system for a water analysis sensor cartridge includes a water analysis sensor cartridge configured to be interchangeable. The water analysis sensor cartridge comprises at least two different sensor membranes. A transport container cup comprises, for each of the at least two different sensor membranes, a separate moist chamber. Each separate moist chamber comprises one chamber opening and a specific humectant for each of the at least two different sensor membranes.

Abstract: A wastewater analysis sensor cartridge (10) according to the invention is intended to be used only once. It has a liquid-tight housing (20), which contains at least one electrochemical sensor element (30, 32) and at least one reference element (56). Furthermore, the housing (20) contains a sensor element electrolyte tank (40,42) and a reference element electrolyte tank (44). The ion-sensitive membranes (31, 33) of the sensor elements (30, 32) and the housing (20) consist of plastic.

Abstract: Gas-selective electrodes in liquid analyzing devices have a characteristic curve K with a linear portion L and a non-linear portion NL. In the non-linear portion NL, the characteristic previously could only be estimated so that determinations of the concentration were rather inexact. According to the present application, the electrode is rinsed with an acid and the zero point voltage UN at the electrode is determined during the rinsing. Using the zero point voltage UN, the non-linear portion NL of the characteristic K is determined with high precision so that even low concentrations c can be determined with great accuracy.

Abstract: A method for automatically determining the concentration of nitrite in a liquid sample includes: determination of the extinction of the liquid sample at a wavelength ? of 150-250 nm, addition of a nitrite reducing agent to the liquid sample, determination of the extinction of the reduced liquid sample at a wavelength ? of 150-250 nm, and determination of the nitrite concentration from the difference between the concentration values obtained from the extinctions of the non-reduced and the reduced liquid samples.

Abstract: A wastewater analysis sensor cartridge (10) according to the invention is intended to be used only once. It has a liquid-tight housing (20), which contains at least one electrochemical sensor element (30, 32) and at least one reference element (56). Furthermore, the housing (20) contains a sensor element electrolyte tank (40,42) and a reference element electrolyte tank (44). The ion-sensitive membranes (31, 33) of the sensor elements (30, 32) and the housing (20) consist of plastic.

Abstract: A method for automatically determining the concentration of nitrite in a liquid sample includes: determination of the extinction of the liquid sample at a wavelength ? of 150-250 nm, addition of a nitrite reducing agent to the liquid sample, determination of the extinction of the reduced liquid sample at a wavelength ? of 150-250 nm, and determination of the nitrite concentration from the difference between the concentration values obtained from the extinctions of the non-reduced and the reduced liquid samples.

Abstract: Gas-selective electrodes in liquid analyzing devices have a characteristic K with a linear portion L and a non-linear portion NL. In the non-linear portion NL, the characteristic can only be estimated so that these determinations of the concentration are rather inexact. According to the present method, the electrode is rinsed with an acid and the zero point voltage at the electrode is determined during the rinsing. Using the zero point voltage UN thus quickly obtained, the non-linear portion NL of the characteristic K can be determined with high precision so that even low concentrations c can be determined with great accuracy.