From Isonitriles to Unsaturated NHC Complexes of Gold,Palladium and Platinum

In a modular template synthesis, unsaturated NHC complexes of gold, palladium and platinum were synthesized from simple metal salts, isonitriles and amines with acetal or ketal groups. Upon the addition of amines with tethered acetal or ketal moieties to the metal‐activated isonitrile, first nitrogen acyclic carbene (NAC) complexes are formed. These undergo ring closure and elimination to the unsaturated NHC complexes upon addition of acid. This simple strategy opens an attractive and fast approach to NHC complexes of gold, palladium and platinum. The modular approach allows a fast modification and is well‐suited for the synthesis of unsymetrically and symmetrically substituted unsaturated NHC complexes.

     

Large‐Scale Preparation of Polymer Nanocarriers by High‐Pressure Microfluidization

Polymer nanocarriers are used as transport modules in the design of the next generation of drug delivery technology. However, the applicability of nanocarrier‐based technology depends strongly on our ability to precisely control and reproduce their synthesis on a large scale because their properties and performances are strongly dependent on their size and shape. Fundamental studies and practical applications of polymer nanocarriers are hampered by the difficulty of using the current methods to produce monodispersed nanocarriers in large quantities and with high reproducibility. Here, a versatile and scalable approach is reported for the large‐scale synthesis of polymer nanocarriers from water‐in‐oil miniemulsions. This method uses microfluidization to perform a controlled emulsification and is proven to be effective to prepare nanocarriers of different biopolymers (polysaccharides, lignin, proteins) up to 43 g min^?1 with reproducible size and distribution.     

Robust design optimization for improving automotive shift quality

Already in the design process of automatic transmissions, robustness should be considered as important design goal to assure high shift quality and reliability in the presence of environmental, operating or manufacturing uncertainties. Beside the implementation of adaption algorithms for clutch control, this may also be achieved by using robust design strategies. By such a procedure, mean values for best mean shift quality, and variances for highest robustness against change of system parameters are minimized simultaneously. In the paper, such an approach is developed for transmission calibration. Comparison with a deterministically found design shows improved performance and validates the eligibility of the proposed design strategy.     

OctoMap: an efficient probabilistic 3D mapping framework based on octrees

Three-dimensional models provide a volumetric representation of space which is important for a variety of robotic applications including flying robots and robots that are equipped with manipulators. In this paper, we present an open-source framework to generate volumetric 3D environment models. Our mapping approach is based on octrees and uses probabilistic occupancy estimation. It explicitly represents not only occupied space, but also free and unknown areas. Furthermore, we propose an octree map compression method that keeps the 3D models compact. Our framework is available as an open-source C++ library and has already been successfully applied in several robotics projects. We present a series of experimental results carried out with real robots and on publicly available real-world datasets. The results demonstrate that our approach is able to update the representation efficiently and models the data consistently while keeping the memory requirement at a minimum.     

Drop tower experiments on sticking, restructuring, and fragmentation of preplanetary dust aggregates

For the determination of the aggregation efficiency of preplanetary dust, we performed impact experiments with fractal dust aggregates in the drop tower Bremen. We found that for the lowest impact velocities, the dust aggregates, which consisted of micron-sized, monodisperse SiO₂ spheres, hit and stuck with no measurable impact restructuring. For intermediate collision velocities, compact aggregate structures formed, and at the highest impact velocities, aggregates were fragmented. Our experimental results are in quantitative agreement with a numerical dust aggregate collision model (Dominik, C., Tielens, A. G. G. M. 1997, Astrophysical Journal vol. 480, p. 647), when the latest experimental values for the rolling-friction and break-up energies are used. However, the presence of a rarefied gas flow, in which the incoming aggregates were embedded, increased the threshold velocity for sticking. Although the impinging aggregates were disintegrated at high impact velocities, the resulting fragments were dragged back to the target on which they could stick due to a then considerably lower collision velocity. This aerodynamically-supported aggregation process might be responsible for the rapid growth of preplanetary bodies in the size range from ∼0.1 m to ∼10 m. Such a rapid growth is necessary to prevent a loss of most of the solid bodies of these sizes due to gas-drag-induced fast orbital decay.     

Bericht vom FNN/ETG-Tutorial Schutz- und Leittechnik 2010

Am 9. und 10. Juni 2010 fand in Ulm das "Tutorial Schutz- und Leittechnik 2010" statt, welches vom Forum Netztechnik/Netzbetrieb im VDE (FNN) und der Energietechnischen Gesellschaft im VDE (ETG) in Zusammenarbeit mit der OGE (?sterreichische Gesellschaft für Energietechnik im OVE), der ETG von Electrosuisse und Oesterreichs Energie (vormals VE?) veranstaltet wurde. Das Tutorial war mit rund 300 Teilnehmern sehr gut besucht, was die Aktualit?t der gew?hlten Themen unterstreicht. Die Veranstaltung bestand aus Plenum-Vortr?gen und -Diskussionen, Workshops sowie einer Fachausstellung und bot dem Fachpublikum auf Hersteller- und Anwenderseite die Gelegenheit, die aktuellen Entwicklungen auf dem Gebiet der Schutz- und Leittechnik kennen zu lernen, sich zu informieren und auszutauschen. Zudem war auch eine Postersession in das Programm integriert.     

The radioecology of the grapevine. 1. The transfer of nuclear weapons fallout from the soil into wine

In a field investigation (1983-1985) comprising eight places of the most important viticultural regions in the Federal Republic of Germany, the contents of the radionuclides tritium (3H), carbon-14 (14C), strontium-90 (90Sr), and cesium-137 (137Cs) in air, soils, leaves of the vine, grapes and wine were measured and site-specific transfer factors were calculated. Data concerning soil parameters, climatic conditions, cultivation and vinification were collected. The tritium content of all samples was 10 Bq/l water of combustion, independent of location and year. The specific activity of 14C in the atmosphere and in biological material was 0.22 Bq/g carbon, independent of site and year. 90Sr contents of soils fluctuated between 0.7 and 3.5 Bq/kg dry matter. The mean content of leaves was 2 Bq/kg fresh material, of grapes 0.035 Bq/kg and of wine 0.008 Bq/l. 137Cs content of soils fluctuated between 1.3 and 7.9 Bq/kg dry matter. The mean content of leaves was 0.098 Bq/kg fresh material, of grapes 0.021 Bq/kg and of wine 0.0085 Bq/l. A relation between transfer of radionuclides and soil parameters and between the contents of grapes and wine was not recognizable. While cultivar-specific differences were not observed in grapes, red wines contained somewhat more 137Cs than white wines. Transfer factors soil grapes were 0.027 for 90Sr and 0.0057 for 137Cs. Site-specific influences such as soil parameters, climate, cultivation, vinification and differences between years led to a relatively small fluctuation of values. An influence of the nuclear power station Neckarwestheim has not been found in any of the radionuclides.     

22nm光刻技术前景(英文)

在国际半导体技术蓝图(ITRS)指定的22nm节点中[1],该产业将在两种竞争的光刻解决方案中进行选择,这将取决于其产品的发展路线图。在某些情况下,业界甚至可能会同时使用两种方案。这两种竞争方案就是极紫外光刻技术(EUVL)和32nm节点由193nm浸没式双重图形光刻(DPL)扩展到多图形的光刻技术。讨论了两种技术,比较了两种技术所需的关键解决方案的现状,以及存在的挑战。