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61.
Holger Becker Reinhard Caspary Christian Toepfer Manfred V. Schickfus Siegfried Hunklinger 《Journal of Modern Optics》2013,60(9):1715-1723
Abstract We have developed a fixed beam direct writing laser lithography system with a minimum feature size of 400nm at 457nm wavelength and a writing speed of 4·2mm/s with total system costs of less than 100 000 US$. 相似文献
62.
This study shows an approach to estimate odour intensity in an indoor environment with a multi-gas sensor system. The sensor system uses 38 non-specific gas sensors, each of which responds to a wide range of different volatile compounds. Due to the complexity of indoor air pollution, the study focuses on emissions of building products as one of the major contributors to indoor air quality. The system has been calibrated and tested, combining measurements from gas sensor systems and assessments of odour intensity by a human panel. To find a relation between the sensor signal and the odour intensity, a data processing model has been developed comprising a classification and a class-specific regression method. The model is able to map the odour intensity to the sensor signal pattern in order to predict the odour intensity caused by the investigated building products. Investigations with varying relative humidity have shown a significant influence by the humidity level, which will be considered for future measurements. 相似文献
63.
Bernd Oberdorfer Eva-Maria Steyskal Wolfgang Sprengel Reinhard Pippan Michael Zehetbauer Werner Puff Roland Würschum 《Journal of Alloys and Compounds》2011
The release of excess volume upon recrystallization of ultrafine-grained Ni deformed by high-pressure torsion was measured with a high-precision difference-dilatometer employing constant heating rates in the range from 0.3 to 10 K min?1. The kinetics of the recrystallization process was analyzed according to the Johnson–Mehl–Avrami–Kolmogorov theory adapted to the case of constant heating rates. An effective Avrami exponent of 2 and a value of 1.20 eV for the activation energy of recrystallization was determined. Analysis by the Kissinger method yielded the same result for the activation energy. 相似文献
64.
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66.
Thomas Beer Tobias Meisen Rudolf Reinhard Sergey Konovalov Daniel Schilberg Sabina Jeschke Torsten Kuhlen Christian Bischof 《Production Engineering》2011,5(4):383-391
Computational simulations are used for the optimization of production processes in order to significantly reduce the need
for costly experimental optimization approaches. Yet individual simulations can rarely describe more than a single production
step. A set of simulations has to be coupled to each other to form a contiguous representation of a process chain. Eventually,
simulated results have to be analyzed by domain experts to gather insight from the preformed computations. In this paper,
we propose an IT infrastructure and software tools that aim at a rather non-intrusive way of coupling resources and domain
expert’s knowledge to enable the collaborative setup, execution and analysis of distributed simulation chains. We illustrate
the approach in the domain of materials processing. Beyond means originating from the domain of GRID computing for resource
management, a data integration component assures semantic data integrity between the simulation steps and stores simulation
data in an application independent way. Thus, we can transform this data into native formats for each simulation tool, and
finally into a format that allows for contiguous visualizations and an intuitive, comprehensive analysis of complete simulated
process chains. 相似文献
67.
Wei Xia Johannes H. Bitter Dangsheng Su Jun Qian Martin Muhler 《Diamond and Related Materials》2009,18(1):13-19
Vapor grown carbon fibers (VGCFs) with diameters of several microns were synthesized and investigated by high resolution transmission electron microscopy. It was found that the shell of the VGCFs consisted of densely-packed domains embedded in loosely-packed matrix, and both were highly amorphous. Regular edge planes as observed on the surface of fishbone nanofibers do not exist on VGCFs. Hence, surface treatment is more important for the deposition of catalysts. Ammonium ferric citrate (AFC) was employed for the impregnation of iron, where the high viscosity of the aqueous solution of AFC is beneficial. Calcination was found to be a key step to improve the dispersion of the iron particles, which can be attributed to enhanced interactions between iron and carbon due to the gasification of carbon occurring at the iron–carbon interface. Quantitative analysis by X-ray photoelectron spectroscopy showed that the calcination of the supported AFC led to a higher atomic concentration of iron on the surface, indicating smaller particle size and a higher dispersion. Secondary carbon nanofibers were grown subsequently on the VGCFs from cyclohexane. The specific surface area was enhanced considerably, from less than 1 m2 g? 1 to 106 m2 g? 1 after the growth of the secondary nanofibers. The obtained composites are promising materials as structured support in heterogeneous catalysis. 相似文献
68.
A fiberoptic sensor system was developed for the detection of PAH-coated aerosols. It incorporates a pulsed nitrogen laser for excitation and a monochromator, a photomultiplier and a digital storage oscilloscope for recording of fluorescence decay curves. With a software-realized photon counting technique detection limits less than 100 ng/m3 for most of the PAHs investigated were achieved with NaCl as a substrate (e.g., 20 ng/m3 for benzo(e)pyrene on NaCl). The sensitivity of the system decreased dramatically when PAH adsorbed on carbon aerosol were analyzed. With pyrene on polydisperse NaCl aerosol the formation of excimers was observed and the formation kinetic could be analyzed. With benzo(e)pyrene on NaCl under similar conditions excimer fluorescence was observed but not the formation kinetic. This indicates the formation of micro-crystals of PAHs on aerosol surfaces even at surface coverages Θ ?1. Due to the observed matrix effects experiments were carried out, at which the PAHs were thermally desorbed in advance of the analysis. By this PAH fluorescence was measurable with carbon as matrix. 相似文献
69.
Reinhard Lerch 《e & i Elektrotechnik und Informationstechnik》2002,119(1):a29
ProdukteHeraeus Sensor-Nite
Platinentechnologie auf dem Vormarsch 相似文献70.
Reinhard Lerch 《e & i Elektrotechnik und Informationstechnik》2002,119(1):a29-a30