Untersuchungen zum Erosionsschutz kohlenstoffaserverstärkter Duroplaste

Investigations on erosion protection of carbon-fibre-reinforced thermosetting plastics A double layer system of polyurethane rubber and a metal foil was described by calculation and experiment. There is a significant increase in erosion resistance of a carbon-fibre-reinforced plastic component by application of this system and the experimental results correlate with theoretical estimations. Among the investigated materials surface layers of titanium and a titanium aluminium alloy respectively possess the best resistance in the range of all angles of incidence. The polyurethane rubber also exhibits a very good erosion behaviour under conditions of normal impact as well as at shallow impact angles at room temperature. So the rubber takes care of a good emergency running quality after a destruction of the metal foil. It was found that the relative erosion rate of the protective metal layer decreases with increasing thickness of the rubber. A thickness of about 0,5–0,7 mm of the protective metal layer is sufficient in practice. The titanium foil should have a thickness of about 100–200 m?m for the design life because if the metal foil is too weak it will undergo destruction rather fast under laboratory conditions. There is no change of the well-known erosion mechanisms with the formation of walls around the places of normal impacts as well as grooving and machining at shallow impact angles by application of the double layer system. An increase in temparature up to 80 °C doesn't cause any change of the erosion rate of the investigated metal foils in the double layer system but will influence the erosion of the polyurethane rubber alone. The galvanic deposition of nickel is another way for the use of the double layer system especially for components with a complex geometric shape.     

Polymeric Nanoparticles with Neglectable Protein Corona

The current understanding of nanoparticle–protein interactions indicates that they rapidly adsorb proteins upon introduction into a living organism. The formed protein corona determines thereafter identity and fate of nanoparticles in the body. The present study evaluates the protein affinity of three core‐crosslinked polymeric nanoparticles with long circulation times, differing in the hydrophilic polymer material forming the particle surface, namely poly(N‐2‐hydroxypropylmethacrylamide) (pHPMA), polysarcosine (pSar), and poly(ethylene glycol) (PEG). This includes the nanotherapeutic CPC634, which is currently in clinical phase II evaluation. To investigate possible protein corona formation, the nanoparticles are incubated in human blood plasma and separated by asymmetrical flow field‐flow fractionation (AF4). Notably, light scattering shows no detectable differences in particle size or polydispersity upon incubation with plasma for all nanoparticles, while in gel electrophoresis, minor amounts of proteins can be detected in the particle fraction. Label‐free quantitative proteomics is additionally applied to analyze and quantify the composition of the proteins. It proves that some proteins are enriched, but their concentration is significantly less than one protein per particle. Thus, most of the nanoparticles are not associated with any proteins. Therefore, this work underlines that polymeric nanoparticles can be synthesized, for which a protein corona formation does not take place.     

Efficacy of knife disinfection techniques in meat processing

EU Regulation 853/2004 requires that knives used in meat processing be disinfected by submerging them in hot water (+ 82 °C). Alternative procedures are permitted if the efficacy is proved to be equivalent. In the present study, various time–temperature combinations together with pure water, water with lactic acid (2 %), and the use of ultrasound with and without lactic acid (2%) were investigated. Steel plates were covered with fat and protein and then inoculated with a standardized bacterial contamination assembled according to the composition of bacterial contamination found in a previous field trial conducted with regard to the slaughter of pigs. Several combinations with diverse temperatures and time intervals were tested until no microbial load was detectable by using a wet–dry-swab technique that had previously been tested to ensure maximum bacterial recovery. The following were effective in bringing the tested bacterial flora below the detection limit:

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70 °C water bath for 10 s     

Conversion of articulatory parameters into active shape model coefficients for lip motion representation and synthesis

Speech-driven facial animation combines techniques from different disciplines such as image analysis, computer graphics, and speech analysis. Active shape models (ASM) used in image analysis are excellent tools for characterizing lip contour shapes and approximating their motion in image sequences. By controlling the coefficients for an ASM, such a model can also be used for animation. We design a mapping of the articulatory parameters used in phonetics into ASM coefficients that control nonrigid lip motion. The mapping is designed to minimize the approximation error when articulatory parameters measured on training lip contours are taken as input to synthesize the training lip movements. Since articulatory parameters can also be estimated from speech, the proposed technique can form an important component of a speech-driven facial animation system.     

High Field ESR Spectroscopy on GdO1−x F x FeAs

In the present work we have studied polycrystalline samples of the GdO_1?x F _x FeAs superconductor by means of high field electron spin resonance (HF-ESR) spectroscopy. A set of the samples with different levels of fluorine doping was measured in the frequency range from 10 GHz to 400 GHz in magnetic fields up to 15 T. Surprising results have been obtained on the GdO_0.85F_0.15FeAs sample with the superconducting transition temperature T _c =20 K. Gd ESR gives clear indications of the enhancement of (quasi)-static magnetic correlations which set in below ～80 K and continue to develop even in the superconducting state. This suggests an occurrence of an intimate interplay between magnetism and superconductivity in the FeAs planes which evolves in GdO_1?x F _x FeAs compound upon the fluorine doping.     

Incision of the heart during meat inspection of fattening pigs - A risk-profile approach

Meat inspection in the EU is based on Regulation (EC) 854/2004. Accordingly a risk based meat inspection should be implemented. In this paper, the incision of the heart in pig meat inspection is discussed with respect to efficacy. The incision especially can reveal the presence of endocarditis. Here, Erysipelothrixrhusiopathiae (E. rhusiopathiae) and/or Streptococcussuis (S. suis) are of particular concern. Both agents are regarded to be zoonotic agents. There is some evidence for infection of humans via an alimentary pathway. Hence, the occurrence of E. rhusiopathiae and S. suis is a concern of public health (PH) as well as veterinary public health (VPH). However, other measures, including on-farm disease prevention and diagnosis, seem to be more important for food safety. It is concluded that the incision and inspection of the heart is not justifiable with respect to PH aspects.