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排序方式: 共有9962条查询结果,搜索用时 31 毫秒
1.
Beierlein Dennis Häussermann Dorothea Traa Yvonne Klemm Elias 《Catalysis Letters》2022,152(10):2908-2919
Catalysis Letters - We developed a rapid aging method for Ni/Al2O3 methanation catalysts mimicking the real aging in the actual application. The method is based on hydrothermal deactivation of the... 相似文献
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Rosé Carolyn P. Järvelä Sanna 《International Journal of Computer-Supported Collaborative Learning》2020,15(3):249-255
International Journal of Computer-Supported Collaborative Learning - 相似文献
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Aljalbout Elie Walter Florian Röhrbein Florian Knoll Alois 《Neural Processing Letters》2020,51(3):2751-2764
Neural Processing Letters - Legged locomotion is a challenging task in the field of robotics but a rather simple one in nature. This motivates the use of biological methodologies as solutions to... 相似文献
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The Alkylquinolone Repertoire of Pseudomonas aeruginosa is Linked to Structural Flexibility of the FabH‐like 2‐Heptyl‐3‐hydroxy‐4(1H)‐quinolone (PQS) Biosynthesis Enzyme PqsBC 下载免费PDF全文
Florian Witzgall Tobias Depke Dr. Michael Hoffmann Dr. Martin Empting Prof. Dr. Mark Brönstrup Prof. Dr. Rolf Müller Prof. Dr. Wulf Blankenfeldt 《Chembiochem : a European journal of chemical biology》2018,19(14):1531-1544
Pseudomonas aeruginosa is a bacterial pathogen that causes life‐threatening infections in immunocompromised patients. It produces a large armory of saturated and mono‐unsaturated 2‐alkyl‐4(1H)‐quinolones (AQs) and AQ N‐oxides (AQNOs) that serve as signaling molecules to control the production of virulence factors and that are involved in membrane vesicle formation and iron chelation; furthermore, they also have, for example, antibiotic properties. It has been shown that the β‐ketoacyl‐acyl‐carrier protein synthase III (FabH)‐like heterodimeric enzyme PqsBC catalyzes the last step in the biosynthesis of the most abundant AQ congener, 2‐heptyl‐4(1H)‐quinolone (HHQ), by condensing octanoyl‐coenzyme A (CoA) with 2‐aminobenzoylacetate (2‐ABA), but the basis for the large number of other AQs/AQNOs produced by P. aeruginosa is not known. Here, we demonstrate that PqsBC uses different medium‐chain acyl‐CoAs to produce various saturated AQs/AQNOs and that it also biosynthesizes mono‐unsaturated congeners. Further, we determined the structures of PqsBC in four different crystal forms at 1.5 to 2.7 Å resolution. Together with a previous report, the data reveal that PqsBC adopts open, intermediate, and closed conformations that alter the shape of the acyl‐binding cavity and explain the promiscuity of PqsBC. The different conformations also allow us to propose a model for structural transitions that accompany the catalytic cycle of PqsBC that might have broader implications for other FabH‐enzymes, for which such structural transitions have been postulated but have never been observed. 相似文献
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Steven März 《Energy Efficiency》2018,11(7):1721-1743
The German government aims to achieve virtually climate-neutral building stock by 2050 to tackle climate change. To realise this goal, comprehensive policy packages based on neoclassical economic theory are in place to foster energy efficiency investment. However, in the building sector, there is increasingly a gap between this aspiration and the reality. It is claimed that one of the main reasons for this is that the existing policy framework fails to address the specific characteristics and needs of different groups of building owners. This is a particular challenge in Germany, where 80% of all dwellings are owned privately and 37% are rented out by small private landlords (SPL). Despite the significant numbers of SPL, they often follow black box decision-making processes when considering energy renovations. In this study, the author uses an explanatory model to understand the decision-making processes of SPL, combining theoretical aspects from different research disciplines. This model was applied to a low-demand housing market in a neighbourhood in the Ruhr area. Eighteen semi-structured interviews (each lasting between 37 and 115 min) were conducted, demonstrating that in addition to economic factors, the values, beliefs, norms and routines of SPL—as well as their personal capabilities and contextual factors—play an important role in their decision-making. Based on the findings, recommendations are made for enhancing the effectiveness of existing energy efficiency policies and other supporting instruments (e.g. tenancy law and social legislation), tailored to the specific needs of SPL. 相似文献
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