Abstracted/indexed

Applications like air quality, fire detection and detection of explosives require selective and quantitative measurements in an ever-changing background of interfering gases. One main issue hindering the successful implementation of gas sensors in real-world applications is the lack of appropriate calibration procedures for advanced gas sensor systems. This article presents a calibration scheme for gas sensors based on gas profiles with unique randomized gas mixtures.

Traceably calibrated scanning Hall microscopy (SHM) is a versatile tool for the quantitative characterization of magnetic microstructures. To enable SHM with a resolution in the micrometer range under ambient conditions, two Hall sensor materials, gold and graphene, were investigated. A SHM setup utilizing a 5 μm gold Hall sensor was calibrated. The field sensitivity and the detailed uncertainty budget are discussed. The presented traceable calibration is validated by comparison to simulations.

The new concept of a unified pH scale can be used to compare acidities of different kinds of solvents and their mixtures. The aim of the work was to investigate the robustness of the measurement method with four commercially available glass electrodes for non-aqueous media in comparison with the rather specific type of cell used so far for this measurement. The measurement results in aqueous mixtures of ethanol show good agreement.

The necessity to measure harmonic emissions between 2 and 150 kHz is outlined by several standard committees and electrical utilities. This paper presents a measurement system and its traceable characterization designed to acquire and analyze voltages up to 230 V and currents up to 100 A with harmonics up to 150 kHz that may occur in smart grids. The uncertainty estimation is carried out and described in detail for both the fundamental and suprahmarmonics components.