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61.
Andy Norton 《电子元器件资讯》2010,(7)
下一代网络架构是以10千兆以太网成熟发展和工业面向40千兆及100千兆发展为兴起的.聚集的网络为可升级的开放平台处理数据流创造了新挑战.在聚集的下一代架构基础中,常见部件包括高性能的兆兆位转换和在应用层持续增长的复杂性和迅速成长的应用中能够处理几十千兆数据流的可编程的内容处理器.CloudShield已经设计出新的一系列可编程数据包处理器,能够检验、分类,调试和复制数据包,集成与应用层的动态交互. 相似文献
62.
Aluminum control of phosphorus sorption by lake sediments 总被引:9,自引:0,他引:9
Kopácek J Borovec J Hejzlar J Ulrich KU Norton SA Amirbahman A 《Environmental science & technology》2005,39(22):8784-8789
Release of reactive (phosphate-like) phosphorus (P) from freshwater sediments represents a significant internal P source for many lakes. Hypolimnetic P release occurs under reducing conditions that cause reductive dissolution of ferric hydroxide [Fe(OH)3]. This hypolimnetic P release may be naturally low or artificially reduced by sediment with naturally high or artificially elevated concentrations of aluminum hydroxide [Al(OH)3]. We presentfield and laboratory data for a common extraction analysis of sediments from 43 lakes differing in trophic status, pH regime, climate, and P loading. The results indicate that a simple sequential extraction of sediment may be a useful predictor of sediment's ability to release P. Sequential extractions of sediment P, Al, and Fe by water (H2O), bicarbonate-dithionite (BD), and NaOH (at 25 degrees C) showed that negligible amounts of P would be released from lake sediments during hypolimnetic anoxia if either (1) the molar Al(NaOH-25):Fe(BD) ratio is > 3 or (2) the molar Al(NaOH-25):P(H2O+BD) ratio is > 25. These ratios can be used as operational targets for estimation of sediment P release potential and Al dosing of P-rich sediment to prevent hypolimnetic P release under anoxic conditions. 相似文献
63.
Rider A Perez-Maldonado Barry W Norton Graham L Kerven 《Journal of the science of food and agriculture》1995,69(3):291-298
In interaction of condensed tannins from Desmodium intortum and Lotus pedunculatus and tannic acid (hydrolysable tannin) with salivary mucoproteins (from sheep and goats), plant leaf proteins and bovine serum albumin were evaluated. These studies were carried out over a pH range of 2-0-9-0 and different inorganic ion conditions to simulate conditions in which dietary proteins would interact with tannins in a ruminant digestive tract. Insoluble tannin-protein interactions were found at pH 4–5–5–5 for bovine serum albumin and 3–5–5–5 for plant leaf protein. The present study showed that pH alone was not the sole determinant for tannin-protein complex formation, since tannin-protein complexation was found in the pH range 6-0–6-5 when different inorganic ions were added to the solutions. Insoluble complexes were not formed with salivary proteins, although precipitation by tannic acid was achieved at 5°C. This suggests that tannins may form soluble rather than insoluble complexes with salivary proteins. It was concluded that purified F1 leaf protein (the major protei occurring in leaf tissue) ought to be used as the test protein for evaluating tannin-protein interactions for in vitro assay procedures. Using this method it was calculated that 27–43% and 19–40% of available plant protein may interact with condensed tannins from Desmodium intortum and Lotus pedunculatus, respectively. 相似文献
64.
Reis, Maniaci, Caprariello, Eastwick, and Finkel (see record 2011-04644-001) conducted 2 studies that demonstrate that in certain cases, familiarity can lead to liking—in seeming contrast to the results of our earlier article (see record 2006-23056-008). We believe that Reis et al. (a) utilized paradigms far removed from spontaneous, everyday social interactions that were particularly likely to demonstrate a positive link between familiarity and liking and (b) failed to include and incorporate other sources of data—both academic and real-world—showing that familiarity breeds contempt. We call for further research exploring when and why familiarity is likely to lead to contempt or liking, and we suggest several factors that are likely to inform this debate. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
65.
Andrew D. Norton Richard W. GreenwoodIan Noble Phil W. Cox 《Journal of food engineering》2011,105(1):119-127
The expansion and puffing kinetics of commercial potato starch pellets were examined using a hot air fan oven in order to determine the puffing kinetics. The time for the onset of expansion showed uni-molecular type kinetic behaviour and was modelled by an Arrhenius plot. A pseudo-activation enthalpy for pellet expansion was also determined. The initial moisture content of the commercial pellets was controlled and the changes in the extent of puffing and the pseudo-activation enthalpy were found. The effect of type and quantity of cation in the formulation was then investigated. Expansion occurred even when no cation was added although the presence of cation did improve pellet expansion. The ratio of the native and pre-gelatinized starch in the pellets was also varied and showed to have limited effect on the extent of expansion. The puffing mechanism is discussed in light of these observations. 相似文献
66.
W. M. Higgins D. A. Nelson R. G. Roy R. P. Murosako R. A. Lancaster J. Tower P. Norton 《Journal of Electronic Materials》2013,42(11):3320-3330
This paper reviews the history and technology of a bulk Hg1?x Cd x Te crystal growth process that was developed in the early 1980s at Honeywell Electro-Optics Division (presently BAE Systems, Electronic Solutions). The crystal growth process name, DME, was an acronym for the department name: Detector Materials Engineering. This was an accelerated crucible rotation technique (ACRT) vertical traveling heater method growth process. Crystal growth occurred in the pseudobinary Hg1?x Cd x Te system. ACRT mixing allowed the lower-density, higher-x-value Hg1?x Cd x Te growth nutrient in the upper region of the ampoule to replenish the depleted melt and allowed the growth of constant-x-value, higher-density Hg1?x Cd x Te. The material grown by this research and production growth process yielded single crystals that had improved purity, compositional uniformity, precipitate density, and reproducibility in comparison with solid-state recrystallization and other bulk Hg1?x Cd x Te growth techniques. Radial and longitudinal nonuniformities in x-value for Hg1?x Cd x Te were reduced to <0.0008/cm. The net electrically active background impurities did not exceed 1 × 1014 cm?3. Electron mobilities in excess of 1.5 × 106 cm2/V-s were observed at 77 K. Structural defects of less than 104 cm?2 were measured. Te precipitates were not observed. As a result of these material improvements, long-wavelength infrared (LWIR) photoconductive devices fabricated from DME material had highly desired performance characteristics. 相似文献
67.
P. W. Griffiths B. Norton P. C. Eames S. N. G. Lo 《Building Research & Information》2013,41(3):141-142
The centre of glass thermal performance of evacuated glazing is better than the performance of argon‐filled atmospheric pressure double glazings. Mitigation, or elimination of evacuated glazing edge effects will bring total window thermal performance on par, or better than, competing ‘superwindow’ options; thus increasing the commercial attractiveness of these glazings. The results of the computer‐based thermal modelling at the Universities of Sydney and Ulster compare well with each other and with the infrared thermography measurements at Lawrence Berkeley. 相似文献
68.
The notion that leaders are more effective if they can flex their leadership style to deal with shifting priorities, problems, and situations is receiving an increasing amount of attention from consulting psychologists and applied researchers alike. I discuss how flexible leadership is defined with a variety of concepts in the literature and emphasized in the articles in the special issue of Consulting Psychology Journal: Practice and Research on Developing Flexible and Adaptive Leaders for an Age of Uncertainty (Kaiser, 2010, this issue). By integrating the views of the previous authors, I present flexible leadership as a metacompetency that subsumes multiple, more narrowly defined, components (e.g., a wide behavioral repertoire, a learning orientation to develop it, an ability to remain open to learning in novel situations). A model for applying this conception of flexible leadership is discussed followed by suggestions for further research to help consulting psychologists use these ideas in their practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
69.
I. A. Buyanova A. Murayama T. Furuta Y. Oka D. P. Norton S. J. Pearton A. Osinsky J. W. Dong C. W. Tu W. M. Chen 《Journal of Superconductivity and Novel Magnetism》2010,23(1):161-165
In this work, we address the issue of spin relaxation and its relevance to spin detection in ZnO-based materials, by spin-polarized,
time-resolved magneto-optical spectroscopy. We have found that spin relaxation is very fast, i.e. about 100 ps for donor bound
excitons in wurtzite ZnO, despite of a weak spin–orbit interaction. We also reveal that alloying of ZnO with Cd enhances spin
relaxation, prohibiting ZnCdO/ZnO structures for efficient optical spin detection. On the other hand, a variation in strain
field induced by lattice mismatch with substrates does not seem to lead to a noticeable change in spin relaxation. The observed
fast spin relaxation, together with the limitation imposed by the band structure, are thus identified as the two most important
factors that limit the efficiency of optical spin detection in the studied ZnO-based materials. 相似文献
70.
A compact, pulsed Nd:YAG laser-based instrument has been built to measure in situ absolute gas temperatures in large industrial furnaces by use of spontaneous anti-Stokes Raman scattering. The backscattering configuration was used to simplify the optics alignment and increase signal-to-noise ratios. Gated signal detection significantly reduced the background emission that is found in combustion environments. The anti-Stokes instead of the Stokes component was used to eliminate contributions to spectra from cold atmospheric nitrogen. The system was evaluated in a methane/air flame and in a bench-top oven, and the technique was found to be a reliable tool for nonintrusive absolute temperature measurements with relatively clean gas streams. A water-cooled insertion probe was integrated with the Raman system for measurement of the temperature profiles inside an industrial furnace. Gas temperatures near 1500-1800 K at atmospheric pressure in an industrial furnace were inferred by fitting calculated profiles to experimental spectra with a standard deviation of less than 1% for averaging times of ~200 s. The temperatures inferred from Raman spectra are in good agreement with data recorded with a thermocouple probe. 相似文献