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121.
Olaf Kessler 《Surface & coatings technology》2006,201(7):4046-4051
For a proper use of coated tools and components excellent coating properties as well as excellent substrate properties of the coating/substrate composite are necessary. A well known example is the load support of hard steel substrates for thin wear resistant coatings. Therefore coating processes must be combined with heat treatment processes of the substrates, whereby several practical processing constraints like order and compatibility of the applied treatment procedures must be considered. The combination of CVD-coating plus laser beam hardening is an example of a post coating heat treatment. Applications may be possible for large forming tools made of high alloyed tool steels, which nowadays are usually through hardened after CVD-coating. Laser beam hardening offers the possibility, to harden only the highly loaded edges of the tools. The advantages of this combination are short process time, less distortion and compressive residual stresses in the substrate surface. CVD-coatings can endure laser beam hardening with suitable parameters. The influence of CVD TiN-coated steel substrates and laser beam hardening parameters on microstructures and properties of coating/substrate compounds have been investigated. Special attention was paid to overlapping hardening zones, which may occur at the start and end points of a laser hardened track. In summary, the combination of coating and heat treatment processes show a high potential to produce coating/substrate compounds with excellent coating properties as well as excellent substrate properties. 相似文献
122.
Leonard Staphorst Mike Holland Leon Pretorius Marthinus Willem Pretorius 《Engineering Management Journal; EMJ》2017,29(1):26-44
Strengthening intellectual property rights for publicly financed research and development (R&D) ensures that research organizations maximize the full national value of the intellectual property that they generate, but potential negative spillover effects on the perceived value of a research alliance might deter an existing alliance partner from continued collaboration or a potential alliance partner from future collaboration. This study, performed in 2010 within the context of the Council for Scientific and Industrial Research in South Africa, aimed to develop a structural equation modeling-based value-mediation governance decision-making model that will enable engineering managers at publicly financed R&D organizations to select optimal governance modes for the research alliances they are establishing to grow their organizations’ R&D capabilities. 相似文献
123.
Frank Herzel Sabbir A. Osmany Kai Hu Klaus Schmalz Ulrich Jagdhold J. Christoph Scheytt Oliver Schrape Wolfgang Winkler Rüdiger Follmann Dietmar Köther Thorsten Kohl Olaf Kersten Thomas Podrebersek Heinz-Volker Heyer Frank Winkler 《Analog Integrated Circuits and Signal Processing》2010,65(1):21-32
We present an integrated fractional-N low-noise frequency synthesizer for satellite applications. By using two integrated VCOs and combining digital and analog tuning techniques, a PLL lock range from 8 to 12 GHz is achieved. Due to a small VCO fine tuning gain and optimized charge pump output biasing, the phase noise is low and almost constant over the tuning range. All 16 sub-bands show a tuning range above 900 MHz each, allowing temperature compensation without sub-band switching. This makes the synthesizer robust against variations of the device parameters with process, supply voltage, temperature and aging. The measured phase noise is ?87 dBc/Hz and ?106 dBc/Hz at 10 kHz and 1 MHz offset, respectively. In integer-N mode, phase noise values down to ?98 dBc/Hz at 10 kHz and ?111 dBc/Hz at 1 MHz offset, respectively, were measured. 相似文献
124.
JJ Holland 《Canadian Metallurgical Quarterly》1996,14(4):431-432
125.
There were 35 oesophageal intubations in the first 2000 incidents reported to the Australian Incident Monitoring Study (AIMS). These reports confirm existing impressions that misplacement of the endotracheal tube can occur in trained as well as untrained hands, and that auscultation is an unreliable test. On the other hand, the value of capnography is emphasised, with no false positives in the 16 cases in which the instrument was used. There was one false negative. Over the 4 years of the AIMS study, reports have declined in frequency. It is possible that the early detection of oesophageal intubation by capnography has altered its status to the extent that anaesthetists no longer regard it as a "critical" incident. It is highly recommended that the presence of the expected concentration of carbon dioxide in expired air be confirmed by capnography immediately after any endotracheal intubation. 相似文献
126.
Ming Li Stephen D. Holland William Q. Meeker 《Journal of Nondestructive Evaluation》2011,30(3):172-178
This paper describes the estimation of probability of detection (POD) for a vibrothermography inspection procedure. The results
are based on a large scale experiment on specimens with two different kinds of metal containing fatigue cracks. The specimens
were tested independently at three inspection sites: Iowa State University (ISU), Pratt and Whitney (PW) and General Electric
(GE). Despite the substantially different vibrothermography configurations and experimental measurement responses, the estimated
PODs as function of crack length and dynamic stress were similar for all three inspection sites, which make quantitative POD
comparisons possible across different inspection sites. 相似文献
127.
128.
It is the aim of this paper to present an overview of 50 years of dedicated work on electron beam lithography and to highlight the contributions from Jena/Germany starting in the 1960’s. Already in 1958, the forming of contamination layers was a well known, although unwanted in most cases, side effect in electron microscopy. Buck (D.A. Buck et al., in: Proc. Eastern Joint Computer Conf., 1959, pp. 55–59.) from MIT intended to utilize this effect to create an etching mask for his vapor deposition layers. In the 1960’s there was a huge interest in investigating and utilizing the advantages of electron beam lithography. This was the situation when the Jena group entered the community. A decade later, at the spring trade fair in Leipzig/Germany, the group presented a Gaussian beam lithography system (1977) as well as a variable-shaped beam system (1978) to the world. Until now more than 100 tools have been manufactured and sold. A persistent analysis of and interaction with the customers’ needs delivers a good feedback and ensures the permanent high quality of the state of the art lithography products. The group pioneered and shaped the development of e-beam systems with respect to specific aspects. 相似文献
129.
Richard A. Holland 《Journal of the Royal Society Interface》2010,7(52):1617-1625
In migratory passerine birds, strong magnetic pulses are thought to be diagnostic of the remagnetization of iron minerals in a putative sensory system contained in the beak. Previous evidence suggests that while such a magnetic pulse affects the orientation of migratory birds in orientation cages, no effect was present when pulse-treated birds were tested in natural migration. Here we show that two migrating passerine birds treated with a strong magnetic pulse, designed to alter the magnetic sense, migrated in a direction that differed significantly from that of controls when tested in natural conditions. The orientation of treated birds was different depending on the alignment of the pulse with respect to the magnetic field. These results can aid in advancing understanding of how the putative iron-mineral-based receptors found in birds'' beaks may be used to detect and signal the intensity and/or direction of the Earth''s magnetic field. 相似文献
130.