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991.
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993.
Emilija Panti Antonio Bento Dieter Hauff Federica Petricca Franz Prbst Wolfgang Seidel 《Optical Materials》2009,31(10):1398
An important aspect of dark matter search experiments is the active background reduction by identification of the type of particle interacting in the detector. In CRESST this is achieved by a simultaneous detection of heat and light produced by an interaction in a scintillating crystal. The overall light collection efficiency is a crucial parameter in order to achieve enough sensitivity to measure the small fraction of the deposited energy that is emitted as scintillation light. For this purpose, a thin superconducting lead film deposited on sapphire substrates has been tested as an alternative light absorber to a silicon absorber. The first results already show a better light absorption of the lead film. Other superconducting films are also being analyzed. 相似文献
994.
Paul C. Millett Anter El-Azab Srujan Rokkam Michael Tonks Dieter Wolf 《Computational Materials Science》2011,50(3):949-959
We present a phase-field model of void formation and evolution in irradiated metals by spatially and temporally evolving vacancy and self-interstitial concentration fields. By incorporating a coupled set of Cahn–Hilliard and Allen–Cahn equations, the model captures the processes of point defect generation and recombination, annihilation of defects at sinks, as well as void nucleation and growth in the presence of grain boundaries. Illustrative results are presented that characterize the rate of void growth or shrinkage due to supersaturated vacancy or interstitial concentrations, void nucleation and growth kinetics due to cascade-induced defect production, as well as void denuded and peak zones adjacent to grain boundaries. 相似文献
995.
Cornelia Bellmann Victoria Albrecht Jan Roth John Cremers Dieter Pleul Karina Grundke 《真空研究与实践》2010,22(6):26-30
Modification of non‐polar polymer surfaces In numerous technological relevant processes the adhesion in compound systems is of central importance. It concerns for example surface coatings and the manufacturing of composites. Particular problems result at the compounding of polyolefins, silicones and fluoropolymers due to their very low surface energy. The modification of such polymer surfaces with the aim of functionalisation and with it of increasing the surface energy results in an improvement of adhesion properties of the materials. A well‐established procedure, particularly in the automotive industry, is the flame treatment of the surfaces. However, a defined chemical modification of the surface depends on many parameters and thus is very difficult to standardize. A defined change of the surface can be better achieved through a targeted plasma treatment, in which in our case the surface is stabilized by a subsequent wet chemical process step. 相似文献
996.
Koen De Turck Stijn De Vuyst Dieter Fiems Herwig Bruneel Sabine Wittevrongel 《Wireless Networks》2013,19(5):831-842
There is a considerable interest nowadays in improving energy efficiency of wireless telecommunications. The sleep-mode mechanism in WiMAX (IEEE 802.16) and the discontinuous reception (DRX) mechanism of LTE are prime examples of energy saving measures. Recently, Samsung proposed some modifications on the sleep-mode mechanism, scheduled to appear in the forthcoming IEEE 802.16m standard, aimed at minimizing the signaling overhead. In this work, we present a performance analysis of this proposal and clarify the differences with the standard mechanism included in IEEE 802.16e. We also propose some special algorithms aimed at reducing the computational complexity of the analysis. 相似文献
997.
Dieter Ernst 《Industry and innovation》2005,12(3):303-335
998.
Thomas Niendorf Stefan Leuders Andre Riemer Hans Albert Richard Thomas Tröster Dieter Schwarze 《Metallurgical and Materials Transactions B》2013,44(4):794-796
For additive manufacturing of metals, selective laser melting can be employed. The microstructure evolution is directly influenced by processing parameters. Employing a high energy laser system, samples made from austenitic stainless steel were manufactured. The microstructure obtained is characterized by an extremely high degree of anisotropy featuring coarse elongated grains and a 〈001〉 texture alongside the build direction during processing. Eventually, the anisotropy of the microstructure drastically affects the monotonic properties of the current material. 相似文献
999.
Tilo Schulz Bernd Lychatz Nicole Haustein Dieter Janke 《Metallurgical and Materials Transactions B》2013,44(2):317-327
The use of fluorides in continuous casting powder leads to the desired reduction of melting temperature to less than 1573 K (1300 °C) as well as to lowering the viscosity below 10 dPas. With an equilateral use of alkalis, the tendency to form volatile fluorine compounds rises. The effect of these components on the structure of the casting slags can be described with the NBO/T-ratio. Should the full effect of fluorides to be used for structural modification of the slags, the other components have to be inhibited by compound formation so as to prevent them from forming gaseous fluoride. If the fluoride content in the continuous casting slag is represented by means of fluorspar, the influence on the NBO/T-ratio can be described with the impact factor 4.0. 相似文献
1000.
The impedance spectra of Rh(111) in aqueous HCl solutions have been measured as function of potential. In the double layer region, just as for other platinum group metals, the equivalent circuit of the interface is a circuit of a Rad-W-Cad element combination parallely connected to a Cdl capacitance; whereas at the H+/Cl− adsorbate exchange peak an additional parallel Rad,2-Cad,2 branch appears in the equivalent circuit. The (Rad-W-Cad) and the Rad,2-Cad,2 branches were demonstrated to be due to chloride and hydrogen adsorption, respectively. Due to the same anion appearing in the charging of Cad and Cdl the two branches are coupled to each other. 相似文献