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171.
This paper presents results on the influence of the nonionic surfactant on the properties of vinyl acetate/VeoVa10® and vinyl acetate/ethylene emulsions and paints made thereof. Emulsions were prepared in which the concentration of the nonionic surfactant and its degree of ethoxylation were varied. An increase of the nonionic emulsifier concentration and of the length of the ethylene oxide chain leads to dispersions with smaller particles and higher viscosities. Using these emulsions as binders in high pigmented paints, it was observed that the pigment binding capacity of the interior paints goes through a maximum which is located at a emulsifier concentration of about 2–3% and at a degree of ethoxylation of 17–28 mol ethylene oxide (EO). In (semi-) gloss paints, the gloss of the paint films improves with an increase of the emulsifier concentration and reaches a constant value at around 4% or a degree of ethoxylation of ca. 17 EO-moieties per molecule. The blocking of the films shows a drastic increase at a concentration above 4% and at a chain length of greater than 17 EO-moieties.  相似文献   
172.
By their nature, mixed-signal circuits have to be tested for both structural integrity and parametric performance. For the example of data converters we review test pattern selection strategies geared towards structural and performance testing. We introduce a novel test pattern selection strategy that merges both objectives, and by that we achieve a significant reduction in the size of the set of test patterns applied on the production line.  相似文献   
173.
Architectural concepts are presented aimed at future multimedia processing schemes. Starting from an analysis of current and future multimedia applications, specific computational requirements are derived. It will be shown that multimedia applications benefit from an exhaustive and flexible exploitation of parallelism. Three architectural concepts—reconfigurable computing, simultaneous multithreading, and associative controlling—are presented, and their potential to increase further the performance on future multimedia applications is investigated.  相似文献   
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175.
We find a regularized formula for the entanglement-assisted (EA) capacity region for quantum multiple-access channels (QMAC). We illustrate the capacity region calculation with the example of the collective phase-flip channel which admits a single-letter characterization. On the way, we provide a first-principles proof of the EA coding theorem based on a packing argument. We observe that the Holevo-Schumacher-Westmoreland theorem may be obtained from a modification of our EA protocol. We remark on the existence of a family hierarchy of protocols for multiparty scenarios with a single receiver, in analogy to the two-party case. In this way, we relate several previous results regarding QMACs.  相似文献   
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Since the early 1970s, it was argued that shifts from relatively smaller to larger youth cohorts in the labor force raise the unemployment rate. In contrast, using US state-level data, two studies come to a contrary conclusion. I provide a theoretical framework for local labor markets that considers age cohort differences in labor market characteristics. Using a spatial panel data model and US county-level data (2000–2014), the estimates provide strong evidence that aging of the working-age population reduces overall unemployment by almost 1 percentage point. Long-run effects that consider local feedbacks are even larger.  相似文献   
179.
Iterative type I polyketide synthases (PKSs) from fungi are multifunctional enzymes that use their active sites repeatedly in a highly ordered sequence to assemble complex natural products. A phytotoxic macrolide with anticancer properties, 10,11‐dehydrocurvularin (DHC), is produced by cooperation of a highly reducing (HR) iterative PKS and a non‐reducing (NR) iterative PKS. We have identified the DHC gene cluster in Alternaria cinerariae, heterologously expressed the active HR PKS (Dhc3) and NR PKS (Dhc5) in yeast, and compared them to corresponding proteins that make DHC in Aspergillus terreus. Phylogenetic analysis and homology modeling of these enzymes identified variable surfaces and conserved motifs that are implicated in product formation.  相似文献   
180.
Streptomyces hygroscopicus is a natural producer of geldanamycin. Mutasynthetic supplementation of an AHBA‐blocked mutant with all possible monofluoro 3‐aminobenzoic acids provided new fluorogeldanamycins. These showed strong antiproliferative activity and inhibitory effects on human heat shock protein Hsp90. Binding to Hsp90 in the low nanomolar range was determined from molecular modelling, AFM analysis and by calorimetric studies.  相似文献   
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