Selective and self-validating breath-level detection of hydrogen sulfide in humid air by gold nanoparticle-functionalized nanotube arrays

We demonstrate the selective detection of hydrogen sulfide at breath concentration levels under humid airflow,using a self-validating 64-channel sensor array ba...     

工艺气体消耗近于零的气体渗碳法

热处理炉,尤其是渗碳及淬火炉,都是连续不断地向炉内通入工艺气体。尽管工艺气体的消耗相当可观,也是热处理成本的一部分,但到目前为止,所通入的工艺气体都是通过废气口烧掉了。本文所述的技术是将工艺气体催化再生后,再送回热处理炉中,渗碳淬火炉的工艺气体消耗量可节省高达90％。本文重点介绍了新的再生技术的概念、实施以及工业应用的效果。     

On modeling the Wilson terminal in the boundary and finite element method

In clinical electrocardiography, the zero-potential is commonly defined by the Wilson central terminal. In the electrocardiographic forward and inverse problem, the zero-potential is often defined in a different way, e.g., by the sum of all node potentials yielding zero. This study presents relatively simple to implement techniques, which enable the incorporation of the Wilson Terminal in the boundary element method (BEM) and finite element method (FEM). For the BEM, good results are obtained when properly adopting matrix deflation for modeling the Wilson terminal. Applying other zero-potential-definitions, the obtained solutions contained a remarkable offset with respect to the reference defined by the Wilson terminal. In the inverse problem (nonlinear dipole fit), errors introduced by an erroneous zero-potential-definition can lead to displacements of more than 5 mm in the computed dipole location. For the FEM, a method similar to matrix deflation is proposed in order to properly consider the Wilson central terminal. The matrix obtained from this manipulation is symmetric, sparse and positive definite enabling the application of standard FEM-solvers.     

省时节能的iFlash间歇式前处理／染色工艺

介绍了iFlash间歇式前处理／染色系统的特点，如低温低碱漂白、高效皂洗等；就加工时间、处理效果及加工成本与常规前处理／染色工艺进行了比较。实践证明，iFlash系统具有省时、省水、节能、环保、改善织物性能等特点。     

Epitaxial n- and p-type Emitters for High Efficiency Solar Cell Concepts

Reducing the module prices by increasing the efficiency of solar cells is one of the major challenges in today＇s photovoltaic research. The emitter formation by epitaxial growth offers a cost-efficient and faster alternative to the standard furnace diffusion process. The efficiency potential of epitaxial emitters 〉 22% has already been proven using a single wafer, low pressure, chemical vapour deposition tool. The purpose of this work is to show the potential of epitaxially grown emitters by APCVD （atmospheric pressure chemical vapour deposition） compared to diffused emitters. The APCVD formation of epitaxial emitters at 1,050 ~C can be realised as high throughput inline process and only takes 1-2 min, whereas the diffusion process using POCI3 takes up to 60 min. Simulations show an increase in voltage of AVoc = ＋10 mV and a reduction in saturation current ,1o of 30% for the epitaxial emitter. The lifetime experiments of solar cells with epitaxial emitter exhibit a diffusion length Leff〉 750μm and an emitter saturation current of Joe 〈 50 fA/cm2 on a planar 10 Ω2cm p-type FZ wafer. Another important aim of this work is to evaluate the limitations of epitaxial emitters due to high thermal budget, interface recombination and the change of reflective properties on textured wafers due to the deposition process. Solar cell efficiencies up to 18.4% on p-type and 20.0% on n-type wafers presented in this paper underline that the emitter epitaxy by APCVD is a competitive process for the emitter formation.     

Development of a Full Parameterized FE-modeling Tool for Efficient Vibration Investigations on End Windings of Turbo- and Hydro-Generators

End windings of generators are excited to vibrations due to electromagnetic forces which can cause severe damage and noise. To avoid this, it is important to predict the natural frequencies and modes of the end windings with finite elements. Due to the complex structure and unknown boundary conditions, the conventionally calculation of stator end windings has been very difficult and time consuming up to now. This paper describes the development of a full parameterized modeling tool, which allows a quick calculation of natural frequencies during the design phase of the generator. To keep the computing time low, it is important to find a way to get exact calculation results without detailed modeling of all pans. Additionally, special attention was paid to the active part, which has been replaced by spring-damper elements, and the determination of their stiffness via experimental modal analysis combined with finite element calculations.     

Mixers with Microstructured Foils for Chemical Production Purposes

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