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41.
Forschung im Ingenieurwesen - Involute gears are high-stress components used in a variety of drivetrain applications. Small manufacturing tolerances require low measurement uncertainties... 相似文献
42.
Rye bran was added to frankfurter-type sausages and meatballs with the aim of producing low-fat products with increased dietary fibre content. The addition of untreated rye bran to sausages was detrimental, causing a substantial increase in frying loss (20% compared to 13.2%). The addition of rye bran treated with hydrolytic enzymes reduced the frying loss to 15.2–16.4%. The firmness was also improved by the treatments (12.8–14.2 N compared to 8.8 N). Enzymatic treatment of rye bran did not however improve the water-holding capacity or the texture of sausages compared to the rye bran that had only been soaked in water. The reason could be that enzymes degraded the solubilized fraction of the dietary fibre, leaving small fragments that cannot contribute to the water-holding capacity and the texture of the sausages. The benefits of treating rye bran in water were not seen in meatballs, probably due to the more particulate structure of meatballs, which is not as sensitive to additives. 相似文献
43.
This paper examines the interaction between the electric double layers of aggregates. Commonly, rather simplified models are used like the approximation of primary particle interaction (APPI), which just considers the interaction of the closest pair of primary particles having a double layer as if they were isolated. However, for nanoparticles the double layer thickness may be in the same order of magnitude as the particle size or even larger, what leads to a considerable double layer overlap inside the aggregates and between two interacting aggregates. Consequently, such approximations will fail. The paper presents a numerical scheme for the double layer interaction of arbitrarily shaped aggregates, which can e.g. help to establish criteria for the applicability of approximate models. The calculation employs a singularity method, which is based on the linearised Poisson–Boltzmann equation. Additionally, a linear model for charge regulation is implemented. The impact of charge regulation and double layer thickness were studied for fractal DLCA aggregates and hexagonal closed-packed aggregates. 相似文献
44.
Cu/Ni‐Loaded CeO2‐ZrO2 Catalyst for the Water‐Gas Shift Reaction: Effects of Loaded Metals and CeO2 Addition
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Busaya Chamnankid Karin Föttinger Günther Rupprechter Paisan Kongkachuichay 《化学工程与技术》2014,37(12):2129-2134
Two different types of metals (Cu and Ni) and the effect of CeO2 addition to produce a CeO2‐ZrO2 co‐supporter were investigated through the water‐gas shift (WGS) reaction. It was found that the WGS activity could be enhanced with CeO2 addition. At relatively high temperature, Ni‐loaded catalysts exhibited higher CO conversion while Cu‐loaded catalysts demonstrated better performance at low temperatures. The stability and yield of the CO2 and H2 products of the Cu catalysts were higher than those of the Ni catalysts. These results may be caused by an irreversible adsorption of CO on Ni and the reverse WGS reaction occurring on the Ni catalysts. In situ diffuse‐reflection infrared Fourier transform spectroscopy data suggests that the WGS mechanism likely proceeded via formate species. 相似文献
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Søren Linderoth Nikolaos Bonanos Karin V. Jensen Jørgen B. Bilde-Sørensen 《Journal of the American Ceramic Society》2001,84(11):2652-2656
The conductivity and structure of 8-mol%-yttria-stabilized zirconia with additions of nickel oxide has been investigated, both in the as-prepared state and after reduction of NiO in hydrogen. During reduction at 1000°C, the conductivity decreases by 40%–50% and most of the NiO dissolved in the zirconia is exsolved in the form of nickel particles. This is accompanied by the formation of tetragonal zirconia precipitates of size 10–40 nm and by an increase in the lattice parameter. On reoxidation in air at 1000°C, the change in lattice parameter is partly reversed, but the conductivity shows no further changes. 相似文献
47.
Karin Förster-Fromme Regina Schuster-Wolff-Bühring Annette Hartwig Aline Holder Andreas Schwiertz Stephan C. Bischoff Jörg Hinrichs 《International Dairy Journal》2011,21(12):940-948
In a novel pilot plant scale process, lactulose was synthesized enzymatically, operating a maximum batch volume of 170 L. The test product was subjected to a randomized, double-blind, placebo-controlled pilot feeding study. Participants consumed a milk serum drink for 14 days, equalling a daily intake of about 3 g d−1 galactosyl-fructoses. Additionally, the effect of industrially produced lactulose and a placebo drink without lactulose was determined. So far, clinical studies on the prebiotic action of lactulose only focussed on the effects of industrially generated lactulose. The intake of enzymatically synthesized lactulose significantly increased (p = 0.001) faecal bifidobacterial counts, while there was no difference with industrially produced lactulose. Analysis of the compounds showed that the drink with enzymatically synthesized lactulose contained an additional disaccharide, β-1,1-galactosyl-fructose. Presumably, this sugar has a bifidogenic effect and may represent a novel prebiotic. 相似文献
48.
The nature of polymer grafts and substrate shape on the surface degradation of poly(l‐lactide)
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Robertus Wahyu N. Nugroho Karin Odelius Anders Höglund Ann‐Christine Albertsson 《应用聚合物科学杂志》2015,132(47)
Surface grafting of functional polymers is an effective method to alter material properties and degradation behavior. Two different substrate shapes of poly(l ‐lactide) (PLLA), i.e., films and microparticles, were surface‐grafted with hydrophilic monomers, and their surface degradation was monitored. Surface grafting with a hydrophilic and acidic polymer graft [acrylic acid (AA)] induced large alterations in the surface morphology and topography of the films. In contrast, hydrophilic and neutral polymer grafts [acrylamide (AAm)] had no significant effect on the surface degradation behavior, while the PLLA reference and co‐monomeric (AA/AAm) polymer‐grafted samples exhibited intermediate surface degradation rates. The grafted PAA chains induced a local acidic environment on the surface of the substrates, which in turn catalyzed the surface degradation process. This effect was more pronounced in the films than in the microparticles. Thus, the nature of the grafted chains and substrate geometry were shown to affect the surface degradation behavior of PLLA substrates. © 2015 The Authors Journal of Applied Polymer Science Published by Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42736. 相似文献
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Philipp Wolf Alexander Mohr Georgina Gavins Victoria Behr Karin Mörl Prof. Oliver Seitz Prof. Annette G. Beck-Sickinger 《Chembiochem : a European journal of chemical biology》2022,23(6):e202100340
Fine-tuning of G protein-coupled receptor (GPCR) signaling is important to maintain cellular homeostasis. Recent studies demonstrated that lateral GPCR interactions in the cell membrane can impact signaling profiles. Here, we report on a one-step labeling method of multiple membrane-embedded GPCRs. Based on short peptide tags, complementary probes transfer the cargo (e. g. a fluorescent dye) by an acyl transfer reaction with high spatial and temporal resolution within 5 min. We applied this approach to four receptors of the cardiovascular system: the endothelin receptor A and B (ETAR and ETBR), angiotensin II receptor type 1, and apelin. Wild type-like G protein activation after N-terminal modification was demonstrated for all receptor species. Using FRET-competent dyes, a constitutive proximity between hetero-receptors was limited to ETAR/ETBR. Further, we demonstrate, that ETAR expression regulates the signaling of co-expressed ETBR. Our orthogonal peptide-templated labeling of different GPCRs provides novel insight into the regulation of GPCR signaling. 相似文献