Injection Molding of Magnesium Aluminate Spinel Nanocomposites for High‐Throughput Manufacturing of Transparent Ceramics

Transparent ceramics like magnesium aluminate spinel (MAS) are considered the next step in material evolution showing unmatched mechanical, chemical and physical resistance combined with high optical transparency. Unfortunately, transparent ceramics are notoriously difficult to shape, especially on the microscale. Therefore, a thermoplastic MAS nanocomposite is developed that can be shaped by polymer injection molding at high speed and precision. The nanocomposite is converted to dense MAS by debinding, pre-sintering, and hot isostatic pressing yielding transparent ceramics with high optical transmission up to 84 % and high mechanical strength. A transparent macroscopic MAS components with wall thicknesses up to 4 mm as well as microstructured components with single micrometer resolution are shown. This work makes transparent MAS ceramics accessible to modern high-throughput polymer processing techniques for fast and cost-efficient manufacturing of macroscopic and microstructured components enabling a plethora of potential applications from optics and photonics, medicine to scratch and break-resistant transparent windows for consumer electronics

Polymerization of aniline in aqueous sulfuric acid - study by electrochemical thermospray mass spectrometry.

Electrochemical thermospray Mass Spectrometry (ETMS) has proved to be a suitable method for the investigation of electrode processes. The mechanisms for the anodic oxidation of N,N-dialkylanilines in neutral aqueous solution and of phenothiazine in non- aqueous ,methanollammonium acetate electrolyte solution were elucidated. These reactions showed formation of higher oligomers. First experiments were done on the electrochemical polymerization of aniline at a Pt-electrode in sulfuric acid. ETMS allows the detection of soluble products. Experiments with the rotating disc electrode indicate that the polymerization of aniline proceeds via soluble oligomers. Thermospray mass spectra are presented of the aniline/sulfuric acid electrolyte and of the electrochemically generated oligomers. Mass spectrometric cyclic voltamograms of aniline and the oxidation of isotope labeled aniline give information about the structure of dimers and trimers and a first insight in the mechanism of the aniline po lymerization process

Wasserstoffelektrode und Gassensor

The invention proposes a new hydrogen electrode comprising an electrolytic solution arranged in a vessel into which a contact element projects, said invention being characterized by the fact that the vessel also contains hollow glass micropellets which are charged with the pressurized hydrogen. Furthermore, the invention proposes a gas sensor comprising such a hydrogen electrode

Volatile products of electrode reactions in inorganic electrolyte

The investigation technique differential electrochemical mass spectrometry (DEMS) combines cyclic voltammetry with mass spectrometry. DEMS measurements enables to detect online gaseous products formed by electrochemical reactions. A new, simplified experimental set-up is presented, which allows to expand this method to high concentrated electrolyte solutions. For inorganic electrolyte, elaborated for a rechargeable Li/LiCoO2 battery system, the usually DEMS cell is improved as compact thin-layer flow cell. Chlorine evolution - substantial for overcharge protection in this battery system - is examined at Ni and Au electrodes

Produkte und Reaktionsmechanismus der anodischen Oxidation von Phenothiazin - Untersuchung mit der Elektrochemischen Thermospray Massenspektrometrie

Using the Electrochemical Thermospray Mass Spectrometry the potential dependent formation of nonvolatile products can be observed in aqueous electrolytes. We planned to extend this on-line method to electrochemical reactions in organic electrolytes by development of a side beam thermospray ion source. For the test of this experimental set up the anodic oxidation of phenothiazin in ammonium acetate/methanol was examined. The potential dependent formation of different, partly yet unknown products allowed the elucidation of the reaction mechanism