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21.
Liang-Yu Chen Gary W Hunter Philip G Neudeck Dak Knight 《Solid-state electronics》1998,42(12):2209-2214
The surface and interface properties of Pd0.9Cr0.1/SiC Schottky diode gas sensors both before and after annealing are investigated using Auger electron spectroscopy (AES), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). At room temperature the alloy reacted with SiC and formed PdxSi only in a very narrow interfacial region. After annealing for 250 h at 425°C, the surface of the Schottky contact area has much less silicon and carbon contamination than that found on the surface of an annealed Pd/SiC structure. Palladium silicides (PdxSi) formed at a broadened interface after annealing, but a significant layer of alloy film is still free of silicon and carbon. The chromium concentration with respect to palladium is quite uniform down to the deep interface region. A stable catalytic surface and a clean layer of Pd0.9Cr0.1 film are likely responsible for significantly improved device sensitivity. 相似文献
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The authors highlight several possible ways in which the construction industry could lower present emissions of the greenhouse gas, carbon dioxide. It is an excellent discussion document and is recommended reading. 相似文献
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Mark S. Daskin Philip C. Jones 《Computer-Aided Civil and Infrastructure Engineering》1993,8(6):409-421
Abstract: Facility location and customer allocation problems are pervasive in industry and in the private sector. In this paper, we outline a new approach to solving these problems that avoids the need to resort to integer programming techniques. The approach exploits the mathematical structure of the problem as well as characteristics frequently found in applied location/allocation problems. Using this approach, large scale problems are readily solvable on personal computers. We illustrate the approach on a small example and provide computational results based on a real-world application of the technique. Extensions to include additional problem features are also discussed. 相似文献
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Yan T Wong Norbert Dommel Philip Preston Luke E Hallum Torsten Lehmann Nigel H Lovell Gregg J Suaning 《IEEE transactions on neural systems and rehabilitation engineering》2007,15(3):425-434
A neurostimulator application-specific integrated circuit (ASIC) with scalable circuitry that can stimulate 14 channels, has been developed for an epi-retinal vision prosthesis. This ASIC was designed to allow seven identical units to be connected to control up to 98 channels, with the ability to stimulate 14 electrodes simultaneously. The neurostimulator forms part of a vision prosthesis, designed to restore vision to patients who have lost their sight due to retinal diseases such as retinitis pigmentosa and macular degeneration. For charge balance, the neurostimulator was designed to stimulate with current sources and sinks operating together, and with the ability to drive a hexagonal mosaic of electrodes to reduce the electrical crosstalk that occurs when multiple bipolar stimulation sites are active simultaneously. A hexagonal mosaic of electrodes surrounds each stimulation site and has been shown to effectively isolate each site, increasing the ability to inject localized independent charge into multiple regions simultaneously. 相似文献
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Amit Chourasia Steve Cutchin Yifeng Cui Reagan W Moore Kim Olsen Steven M Day J Bernard Minster Philip Maechling Thomas H Jordan 《Computer Graphics and Applications, IEEE》2007,27(5):28-34
This study focuses on the visualization of a series of large earthquake simulations collectively called TeraShake. The simulation series aims to assess the impact of San Andreas Fault earthquake scenarios in Southern California. We discuss the role of visualization in gaining scientific insight and aiding unexpected discoveries. 相似文献
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Tempest Philip R.; White Patricia; Williamson E.Diane; Titball Richard W.; Kelly David C.; Kemp Graham J.L.; Gray Peter M.D.; Forster Simon J.; Carr Frank J.; Harris William J. 《Protein engineering, design & selection : PEDS》1994,7(12):1501-1507
We have used the technique of antibody reshaping to producea humanized antibody specific for the a toxin of Clostridiumperfringens. The starting antibody was from a mouse hybridomafrom which variable (V) region nucleo-tide sequences were determined.The complementarity-determining regions (CDRs) from these Vregions were then inserted into human heavy and light chainV region genes with human constant region gene fragments subsequentlyadded. The insertion of CDRs alone into human frameworks didnot produce a functional reshaped antibody and modificationsto the V region framework were required. With minor frameworkmodifications, the affinity of the original murine mAb was restoredand even exceeded. Where affinity was increased, an alteredbinding profile to overlapping peptides was observed. Computermodelling of the reshaped heavy chain V regions suggested thatamino acids adjacent to CDRs can either contribute to, or distort,CDR loop conformation and must be adjusted to achieve high bindingaffinity. 相似文献
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