Part average analysis – A tool for reducing failure rates in automotive electronics

As the complexity of technical systems increases, it is a matter of course that the quality requirements made on the assemblies, modules and components which are used increase as well. The Part Average Analysis (PAA) reveals a software-based methodical approach which can be used to improve the reliability and availability of technical functions in an efficient manner. The PAA is used to observe anomalies in functions or parameters to measure during the production process, reliably indicating a concealed defect. Components with a high risk of failure are rejected and are not installed in the vehicle (prevention). In this paper, the method will be presented, the mathematical model explained and experiences with automotive suppliers will be reported.     

Light from Maillard reaction: photon counting, emission spectrum, photography and visual perception

Several authors have reported on high-sensitivity measurement of oxygen-dependent low-level chemiluminescence (CL) from Maillard reactions (MR), i.e. nonenzymatic amino-carbonyl reactions between reducing sugars and amino acids (also referred to as nonenzymatic browning). Here we report for the first time, that light from Maillard reactions can be seen by the human eye and also can be photographed. In parallel with visual perception and photography CL was monitored by means of a CL-detection programme of a liquid scintillation counter (LSC, single photon rate counting). CL emission spectrum was recorded by a monochromator-microchannel plate photomultiplier arrangement. CL intensity from reaction of 6-aminocaproic acid with D-ribose (200 mg each) in 5 mL H2O at pH 11 at 95 degrees C was high enough for visual perception after adaptation to absolute darkness. Reaction in dimethylsulphoxide (DMSO) exhibited strongly enhanced CL (10 mg each in 5 mL were sufficient for visual detection) and could be photographed (15 minutes' exposure, ASA 6400); all characteristics of Maillard specific CL (O2-dependence, no CL from nonreducing sugars, inhibition by sulphur compounds) remained. Visual detection of CL and measurement by LSC were in full concordance. The CL emission spectrum showed two broad peaks at around 500 nm and 695 nm. Fluorescence emission of the brown reaction mixture matched the blue-green part of the CL emission spectrum. Emission of visible light during Maillard reactions may partly originate from oxygen-dependent generation of excited states and energy transfer to simultaneously formed fluorescent products of the browning reaction.     

Inductive System for Reliable Magnesium Level Detection in a Titanium Reduction Reactor

Metallurgical and Materials Transactions B - The determination of the Magnesium level in a Titanium reduction retort by inductive methods is often hampered by the formation of Titanium sponge rings...     

SiC devices for advanced power and high-temperature applications

Silicon carbide (SiC) process technology has made rapid progress, resulting in the realization of very promising electronic devices and sensors, enabling advanced solutions in power industry and mobile systems. In particular, for electronics working under harsh environmental conditions, SiC devices reach unprecedented performance. Transfer to production has already started for some applications     

Phenotypic Identification of the Redox Dye Methylene Blue as an Antagonist of Heat Shock Response Gene Expression in Metastatic Melanoma Cells

Repurposing approved and abandoned non-oncological drugs is an alternative developmental strategy for the identification of anticancer therapeutics that has recently attracted considerable attention. Due to the essential role of the cellular heat shock response in cytoprotection through the maintenance of proteostasis and suppression of apoptosis, small molecule heat shock response antagonists can be harnessed for targeted induction of cytotoxic effects in cancer cells. Guided by gene expression array analysis and a phenotypic screen interrogating a collection of 3,7-diamino-phenothiazinium derivatives, we have identified the redox-drug methylene blue (MB), used clinically for the infusional treatment of methemoglobinemia, as a negative modulator of heat shock response gene expression in human metastatic melanoma cells. MB-treatment blocked thermal (43 °C) and pharmacological (celastrol, geldanamycin) induction of heat shock response gene expression, suppressing Hsp70 (HSPA1A) and Hsp27 (HSPB1) upregulation at the mRNA and protein level. MB sensitized melanoma cells to the apoptogenic activity of geldanamycin, an Hsp90 antagonist known to induce the counter-regulatory upregulation of Hsp70 expression underlying cancer cell resistance to geldanamycin chemotherapy. Similarly, MB-cotreatment sensitized melanoma cells to other chemotherapeutics (etoposide, doxorubicin). Taken together, these data suggest feasibility of repurposing the non-oncological redox drug MB as a therapeutic heat shock response antagonist for cancer cell chemosensitization.     

Failure mechanisms and qualification testing of passive components

New electronic architectures and mechatronic integration in automotive and oil-field applications lead to increasing requirements concerning operating temperatures and vibration levels. At the same time, reliability and lifetime have to fulfil strong demands.In the European funded project PROCURE (Program for the development of passive devices used in rough environments) a generic spectrum of passive components needed for electronic control units has been developed. The failure mechanisms, the technological challenges, and the test requirements are highlighted below.     

Combined Electromagnetic Tomography for Determining Two-phase Flow Characteristics in the Submerged Entry Nozzle and in the Mold of a Continuous Casting Model

This article describes experiments on the combined determination of the distribution of liquid metal and argon in the submerged entry nozzle (SEN) and of the flow in the mold of a small-scale physical model of a continuous slab caster. For visualizing the metal distribution in the SEN, mutual inductance tomography (MIT) is applied, while the flow in the mold is determined by contactless inductive flow tomography (CIFT). The results of the latter are validated in part by ultrasonic Doppler velocimetry (UDV). Accompanying measurements provide information about the levels in the tundish and in the mold, as well as on the pressure in the SEN. Depending on the gas flow rate, various flow regimes are identified, among them pressure and mold level oscillations, transitions between double and single vortex flows, and transient single port ejections.