International audienceSilicon nanostructures are synthesized with a DC atmospheric pressure microplasma jet using an Ar/SiH4/H-2 gas mixture. The plasma is characterized by OES and imaged using an EMCCD camera. The effect of hydrogen admixture to the formed structures is studied by transmission electron microscopy. Under specific conditions, crystalline silicon nanoparticles grow in an amorphous matrix investigated by electron energy loss spectroscopy. As-grown silicon nanoparticles are collected in ethanol for dynamic light scattering and photoluminescence measurements. The size distribution peaks at 4nm. The silicon nanocrystals exhibit roomtemperature photoluminescence that peaks at approximate to 415 and approximate to 465 nm

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Al 2 O 3 thin films have been deposited at substrate temperatures between 500• C to 600• C by reactive magnetron sputtering using an additional arbitrary substrate bias to tailor the energy distribution of the incident ions. The films were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR).The film structure being amorphous, nanocrystalline, or crystalline was correlated with characteristic ion energy distributions. The evolving crystalline structure is connected with different levels of displacements per atom (dpa) in the growing film as being derived from TRIM simulations. The boundary between the formation of crystalline films and amorphous or nanocrystalline films was at 0.9 dpa for a substrate temperature of 500 • C. This threshold shifts to 0.6 dpa for films grown at 550 • C.

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nes Baustoffs werden gemäß DIN 41083 [2] durch den Wasseraufnahmekoeffizienten w, der näherungsweise die Wasseraufnahme durch kapillares Saugen definiert, und die diffusionsäquivalente Luftschichtdicke s d , welche die Trocknung bestimmt, beschrieben. Dabei werden folgende Forderungen gestellt: Die Trocknung wird, bedingt durch die Feuchteabgabe, mittels Dampfdiffusion bestimmt. Höhere Dichtigkeit des Mörtels führt einerseits zu geringer Flüssigwasseraufnahme und andererseits zu einem steigenden Diffusionswiderstand. Vereinfacht wird bei wasserabweisenden Außenputzen die Trocknung durch die Feuchteabgabe über Dampfdiffusion begrenzt. Sie erfordern daher eine Relation aus dem w und dem s d Wert. Je höher die Wasseraufnahmefähigkeit, desto Schlagregen führt zu einer Feuchtigkeitsbelastung von Außenwänden und kann insbesondere bei den zunehmend leichter werdenden Mauerwerksbildnern zu Schäden führen. Ein entsprechender Schutz wird in der Regel durch wasserabweisende Putzsysteme realisiert. Ziel der hier vorgestellten Simulationsrechnungen war es, die Wassergehalte im äußeren Bereich der Konstruktionen zu analysieren. Dabei wurde untersucht, ob der derzeit in der DIN 4108-3 verankerte Wasseraufnahmekoeffizient von 0,5 kg/(m 2 √h) ausreichend ist. Dies geschah auch vor dem Hintergrund unterschiedlicher Normungen bei den Prüfverfahren für die Wasseraufnahme (u.a. DIN EN ISO 15148, DIN EN 1015-18). Abschließend wurde betrachtet, welche Putzund Anstrichsysteme günstig sind und welchen Einfluss unterschiedliche Wassergehalte auf den Wärmeschutz haben. Stichworte: Schlagregen Tabelle 1. Kriterien für den Regenschutz von Putzen und Beschichtungen nach DIN 4108-3:2014-11 [2] bei Prüfung nach DIN EN ISO 15148 [3] und DIN EN ISO 12572 Table 1. Criteria for rain protection of plasters and coatings in accordance with DIN 4108-3:2014-11 for testing as specified in DIN 15148 and DIN EN ISO 12572. Kriterien für den Regen schutz Wasser auf nahme koeffizient W w [kg/(m 2 √h)] Äquivalente Luftschicht dicke s d [m] Produkt W w · s d [kg/(m√h)] wasser abweisend ≤ 0,5 ≤ 2,0 ≤ 0,2 Parametric study on the water absorption of different plaster and coating systems using simulations Driving rain results in damp on external walls and causes damage, particularly with increasingly light types of masonry. Appropriate protection is usually provided by water-repellent plaster systems. The aim of the simulations presented here was to analyse the water content in the outer part of the structures. This examined whether the water absorption coefficient of 0.5 kg/(m 2 √h) currently specified in DIN 4108-3 is adequate. It also took account of varying standards for the test procedure for water absorption (incl. DIN EN ISO 15148 and DIN EN 1015-18). Following this, observations were made on which plaster and coating systems are effective and what influence different water content levels have on thermal protection.

Dynamics is a core discipline in Mechanical and Aerospace Engineering programs and with the ubiquitous nature of control in modern-day applications, the field of mechatronics has gained popularity. Mechatronics refers to the field of engineering which integrates the engineering disciplines of mechanical, control, electronics, and computing. To create a testbed to illustrate a tabletop mechatronics system, the paper details the design, and fabrication of an active pendulum whose length can be changed in real-time using solenoids. This permits illustrating two concepts: (1) damping of pendulum oscillations which emulates the sway of a crane and (2) amplification of the oscillations which emulates the pumping of a playground swing. The paper describes the steps prior to experimental validation which includes: modeling, system identification, signal processing, and controller implementation. Numerical simulations are used to prototype the controller and eventually to compare the simulation results to the experimental ones. The results of all the experiments illustrate a close match between the simulated and experimental results. To permit reproduction of the experiment, the design details and code to implement the controllers are posted in a public repository.