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Direct metallization of plastics by high powerimpulse magnetron sputtering Even if polymers are today industrially used for decades the direct metallization of plastics is still a hot topic for research and development. Especially in light of the ban of hexavalent chromium an increasing demand for well‐adhering plastic metallization arises. High power impulse magnetron sputtering HIPIMS is a recent technology that can offer a high potential for successfully solving this challenge. This article focuses on the direct metallization of plastics by HIPIMS. In the frame of the investigations any pretreatment was ignored and the different polymers were directly under vacuum metallized. Compared to conventional mid‐frequency sputtering a significant improvement in adhesion was shown for different polymers. In detail the metallization of Plexiglas (PMMA) was investigated, since this polymer is highly challenging with respect to plasma processes. Due to the UV radiation damage of PMMA during plasma deposition direct metallization is usually not possible. Using ionized deposition it was possible to directly metallize the substrates with excellent adhering films without any interface layers or special pretreatments. The characterization of the substrate‐coating interface showed that for the well adhering films a cohesive fracture, i.e. a fracture within the polymer occurred.  相似文献   
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The antioxidant capacity of cysteine, glutathione, N‐acetylcysteine, and ascorbic acid to reduce Methylene Blue to colourless Leucomethylene Blue was analysed. Interestingly, transient exposure of Leucomethylene Blue to sunlight resulted in a reversible oxidation reaction and thus, provided a fast, easy, and simple quantitative assay to determine antioxidant capacity and photostability of biologically relevant antioxidants.  相似文献   
65.
The methyllysine reader protein Spindlin1 has been implicated in the tumorigenesis of several types of cancer and may be an attractive novel therapeutic target. Small‐molecule inhibitors of Spindlin1 should be valuable as chemical probes as well as potential new therapeutics. We applied an iterative virtual screening campaign, encompassing structure‐ and ligand‐based approaches, to identify potential Spindlin1 inhibitors from databases of commercially available compounds. Our in silico studies coupled with in vitro testing were successful in identifying novel Spindlin1 inhibitors. Several 4‐aminoquinazoline and quinazolinethione derivatives were among the active hit compounds, which indicated that these scaffolds represent promising lead structures for the development of Spindlin1 inhibitors. Subsequent lead optimization studies were hence carried out, and numerous derivatives of both lead scaffolds were synthesized. This resulted in the discovery of novel inhibitors of Spindlin1 and helped explore the structure–activity relationships of these inhibitor series.  相似文献   
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This work reports for the first time the synthesis of ladder polyphenylsilsesquioxanes containing imide building blocks as parts of the main parallel chains. The ladder structure of the synthesized polymers was documented by means of small angle X‐ray scattering (SAXS) measurements. The obtained ladder polymers exhibit stability with respect to decomposition up to temperatures as high as 460°C; additionally, they have melting points far below their decomposition temperatures, which make them interesting candidate materials for thermoplastic processing. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40085.  相似文献   
68.
The ever‐increasing and ever‐changing challenges of the job market require professionals to constantly attend extra occupational education programs. Professionals furthermore express their desire for a compatibility of family and work. Therefore, a general concept for extended vocational training in the field of natural science and technology was developed based on blended learning. As an example, the concept was implemented and tested on the basis of the extended vocational training course “tc‐compactBL” in Chemical Technology.  相似文献   
69.
Protein samples of rapeseed were prepared with different compositions as protein isolate, protein concentrate and acetylated protein concentrate. They showed functional properties which are consolidated in the coating. The manufactured protein samples were tested in a pilot‐scale paperboard coating plant. The results indicated that the use of rapeseed proteins in the coating preparation is technically feasible and that the color and roughness of the coated paperboard show no negative effect on the quality. Industry printing experiments with this coated paperboard achieved the standard quality.  相似文献   
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