Nanoporous Plasmonic Metamaterials

We review different routes for the generation of nanoporous metallic foams and films exhibiting well‐defined pore size and short‐range order. Dealloying and templating allows the generation of both 2D and 3D structures that promise a plasmonic response determined by material constituents and porosity. Viewed in the context of metamaterials, the ease of fabrication of samples covering macroscopic dimensions is highly promising, and suggests more in‐depth investigations of the plasmonic and photonic properties of this material system for photonic applications.     

ZF公司面向中国的高性能变速器

文章介绍了ZF公司为轮式装载机特别研发的WG系列高性能变速器,其产品系列可覆盖9-30吨级的车辆.ZF高性能的动力换档变速器具有简单和坚固的零部件设计、采用精确调整轴承、整体式壳体结构和优越的电控系统等优点.     

Optical Measurement Method of Particle Suspension in Stirred Vessels

Suspending particles in liquids is an important and versatile case for industrial stirring processes. By using advanced optical, non‐invasive measurement techniques like particle image velocimetry (PIV), it is possible to gain deep insights into the involved fluid dynamics without affecting the flow. However, for suspensions, the application of PIV is not trivial since both, suspended and tracer particles are present and need to be discerned during experiments. The here presented method development solves this problem and thus leads to a better insight into turbulent kinetic energy distribution, which can be utilized for process optimization through improved stirred vessel design.     

铝合金薄板搅拌摩擦焊接残余变形的数值分析

大尺寸6056铝合金薄板经过搅拌摩擦焊接实验后出现了严重的面外变形,虽然变形程度小于熔化焊结果,但已经影响到被焊薄板的装配和使用.为详细研究和预测铝合金薄板在搅拌摩擦焊后的残余变形,以焊接实验条件为基础,建立了搅拌摩擦焊接三维有限元热力耦合分析模型.模型中涉及了利用搅拌头工作转矩计算热输入量、工件和卡具之间的接触热传导、随温度变化的材料模型,以及综合考虑搅拌头机械作用等工作.利用该模型可以得到不对称的纵向残余应力结果,残余变形的趋势在整块板上都与实验结果相同,而且变形量和实验测量值之间的误差在20%以内.     

Room Temperature Phase Transition in CeO2 Nanocrystalline Films

The temporal evolution of the lattice parameter of oxygen deficient nanocrystalline cerium oxide films was monitored by X-ray diffraction. It was found that films with lattice parameter of 5.47 {Å} upon deposition undergo large spontaneous expansion, in which the size of the unit cell increases by 0.7% during the course of days. The films with as-deposited lattice parameter larger or smaller than 5.47 Å do not show significant changes. This behavior is consistent with the previously suggested hypothesis of an order-disorder transition of oxygen vacancies and can be viewed as its direct experimental confirmation.     

Structure quality in deep X-ray lithography applying commercial polyimide-based masks

The structure quality of deep X-ray lithography components strongly depends on the quality of the applied X-ray mask. In this article we compare the results obtained with two different mask types. Sophisticated working masks generated by e-beam lithography, soft X-ray lithography and electroplating of gold absorbers on a titanium mask membrane have been fabricated at the Institute for Microstructure Technology, Research Center, Karlsruhe (FZK/IMT), Germany. Prototype masks generated by e-beam lithography, optical lithography and electroplating of gold absorbers on a polyimide mask membrane have been fabricated by Optnics Precision, Japan, with the aim to offer commercially available low cost masks. Both mask types were applied to pattern PMMA resist layers of 300–750 μm thickness at the 2.5 GeV electron storage ring ANKA, Germany, using comparable process parameters. FZK/IMT masks provide microstructures with significantly better structure quality. The layout area, however, is currently limited to 12 cm², and the Ti mask membrane tends to lead to a slight resist surface attack, such as rounding of the resist edges. Optnics masks provide microstructures with reduced structure quality due to sidewall striations (sidewall roughness up to 2 μm) and thermal distortions (of up to 3–5 μm) which limit the potential scope of applications. They could nevertheless potentially be applied as low quality, low cost X-ray masks. High resolution and high accuracy applications, however, require more sophisticated but also more expensive masks, like the Ti-masks from FZK/IMT.     

UML vs. classical vs. rhapsody statecharts: not all models are created equal

State machines, represented by statecharts or state machine diagrams, are an important formalism for behavioural modelling. According to the research literature, the most popular statechart formalisms appear to be Classical, UML, and that implemented by Rhapsody. These three formalisms seem to be very similar; however, there are several key syntactic and semantic differences. These differences are enough that a model written in one formalism could be ill-formed in another formalism. Worse, a model from one formalism might actually be well-formed in another, but be interpreted differently due to the semantic differences. This paper summarizes the results of an informal comparative study of these three formalisms with the help of several illustrative examples. We present a classification of the differences according to the nature of potential problems caused by each difference. In addition, for each difference we discuss how translation between formalisms can be achieved, if at all.