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511.
Sebastian Busch Manuel Ketterer Xenia Vinzenz Christian Hoffmann Katrin Schmitt Jürgen Wöllenstein 《Microsystem Technologies》2014,20(4-5):919-925
We present the development of a novel integrated device for airborne nanoparticle filtering with bioinspired nanoscale functionality. The underlying idea is to investigate the principle of adherent surfaces, e.g. pollen, as a biological model and transfer this functionality into a technology using functionalized microstructured surfaces. This might offer an efficient filtering method for nanoscale airborne particles without the limitations in gas permeability of conventional filters. We investigated the different pollen species for their structural and biochemical surface properties to achieve bioinspired surface functionality on silicon surfaces. The resulting conical structures have sizes from 4 to 20 μm. Depending on structure sizes, the adhesive properties of the surfaces towards aerosol particles could be directly influenced. The surfaces were tested in a demonstrator setup and the collection efficiency visually determined. 相似文献
512.
At the Institute of Metal Forming and Metal-Forming Machines (IFUM), metastable austenitic sheet metal components are examined
concerning the use of their base materials as sensors. By measuring the martensite content at sensitized reference points
of these components, it is possible to draw conclusions about their load history. The local sensitizations are done by defined
elongations and residual stresses using a forming process. This results in a component-inherent sensor acting as a damage
control element, e.g. by registering and storing strains during the component’s life cycle. 相似文献
513.
Zusammenfassung Für Unternehmen, deren Gesch?ftsprozesse unmittelbar von der Verfügbarkeit, Integrit?t und Vertraulichkeit ihrer IT-Infrastruktur
abh?ngen, stellen Penetrationstests ein wesentliches Element einer zukunftsorientierten IT-Sicherheitsplanung dar. Richtig
angewandt, sorgen sie mittel- und langfristig für eine Effizienzsteigerung bei Investitionen sowie ein allgemein hohes Sicherheitsniveau,
wie es die Regelungen des KonTraG und des Sarbanes-Oxley Acts oder das internationale Bankenabkommen Basel II vorgeben.
Diplom-Informatiker und geh?rt als Gesch?ftsführer der SySS GmbH seit 2005 zum Herausgeberbeirat von IT-Sicherheit & Datenschutz
Diplom-Wirtschaftsinformatikerin und als Security Consultant für die SySS GmbH t?tig 相似文献
514.
Katrin F. Domke 《Electrochimica acta》2009,54(21):4829-16771
We have investigated the underpotential deposition (UPD) of silver on high-index platinum single crystals vicinal to the (1 1 1) plane. Carbon monoxide displacement experiments were carried out on Ag-modified Pt(6 6 5) and Pt(3 3 2) stepped single crystal electrodes and examined by means of electrochemical scanning tunneling microscopy (EC-STM) and cyclic voltammetry (CV) in 0.05 M sulfuric acid. Analogous to studies of Pt(1 1 1) by Klein [L.H. Klein, Etude des etats d’adsorption electrochimique sur les electrodes de platine et de rhodium monocristallins modifiees ou non par les adatomes, Ecole Nationale de Chimie de Paris, Universite Paris 6, Paris, 1997] and Domke et al. [K.F. Domke, X.-Y. Xiao, H. Baltruschat, PCCP 10 (2008) 1555], carbon monoxide displaces Ag from stepped Pt electrodes. The present STM studies reveal the formation of small, biatomic thick or thicker Ag clusters on Pt(6 6 5) and Pt(3 3 2) after co-adsorption of CO, extending across step edges, They have a narrow size distribution centred around 10 nm diameter independent of the substrate step density. The desorption of the second Ag adlayer and of CO are monitored electrochemically in two well-separated oxidation peaks at around 0.68 and 0.9 V vs RHE, respectively, whereas the desorption peak of Ag of the first adlayer cannot be completely separated from the early onset of Pt oxidation at approximately 1.13 V vs RHE. 相似文献
515.
Lisa Englert Katrin Silber Dr. Holger Steuber Prof. Dr. Sascha Brass Dr. Björn Over Hans‐Dieter Gerber Andreas Heine Dr. Wibke E. Diederich Prof. Dr. Gerhard Klebe Prof. Dr. 《ChemMedChem》2010,5(6):930-940
Fragment‐based drug discovery has gained a foothold in today's lead identification processes. We present the application of in silico fragment‐based screening for the discovery of novel lead compounds for the metalloendoproteinase thermolysin. We have chosen thermolysin to validate our screening approach as it is a well‐studied enzyme and serves as a model system for other proteases. A protein‐targeted virtual library was designed and screening was carried out using the program AutoDock. Two fragment hits could be identified. For one of them, the crystal structure in complex with thermolysin is presented. This compound was selected for structure‐based optimization of binding affinity and improvement of ligand efficiency, while concomitantly keeping the fragment‐like properties of the initial hit. Redesigning the zinc coordination group revealed a novel class of fragments possessing Ki values as low as 128 μM , thus they provide a good starting point for further hit evolution in a tailored lead design. 相似文献
516.
Anke Jaudszus Katrin Kuhnt Carsten Rohrer Gerhard Jahreis 《European Journal of Lipid Science and Technology》2010,112(12):1393-1396
We analyzed a triacylgylcerol esterified CLA preparation characteristically rich in c9,t11‐CLA and free of t10,c12‐CLA three times within a period of 2${1 \over 2}$ years by GC and silver ion‐HPLC. For the first time, we present data on the long‐term stability of this preparation with regard to the fatty acid profile and the isomeric composition of CLA under certain storage conditions, providing useful information for the planning of long‐term trials. 相似文献
517.
In the past few years, the issue of external alkalis and their influence on ASR in concrete has become more important since several concrete airfield pavements have shown ASR-distress related to the use of alkali-containing airfield deicers based on acetates and formates.Experiments with model pore solutions and cement pastes as well as speciation calculations and ASR performance tests were conducted to investigate possible mechanisms. The obtained results indicate that the solubility of portlandite is increased in the presence of acetate-based and formate-based deicers due to the formation of Ca-acetate and Ca-formate complexes. The additional release of OH− ions from portlandite and the supply of alkalis can initiate and highly accelerate ASR in concretes with reactive aggregates. There is also evidence for a reaction of ettringite with such airfield deicers. 相似文献
518.
In organic synthesis, cyclopropanation reactions are often performed with Simmons-Smith-type reagents or by transition metal catalyzed reactions of olefins with diazo compounds. A novel method for the synthesis of substituted cyclopropanes is described that is based on a two-step reaction sequence. Olefins are reacted with 1,1'-dichlorides in a Ru-catalyzed atom transfer radical addition (ATRA) process and the resulting 1,3-dichlorides are directly converted into cyclopropanes by reductive coupling with magnesium. This one-pot procedure is applicable to a variety of substrates and can be performed in an inter- or intramolecular fashion. 相似文献
519.
520.