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1.
A method has been developed for the frictional assessment of powder lubricants using a shear-box tester similar to that employed by Jenike. One commercial magnesium stearate, three high-purity magnesium stearates and three high-purity magnesium palmitates were assessed using this method. Powders with a well-ordered crystal structure and particle shape have a lower initial maximum coefficient of friction μa. The difference between μa and μb, the equilibrium dynamic friction coefficient, gives an indication of lubricant film-forming propensity. The basic friction equation is obeyed by the powders for most of the load range studied but deviates slightly approaching zero normal load. 相似文献
2.
While scan-based compression is widely utilized in order to alleviate the test time and data volume problems,the overall compression level is dictated not only by the chain to channel ratio but also the ratio of encodable patterns.Aggressively increasing the number of scan chains in an effort to raise the compression levels may reduce the ratio of encodable patterns,degrading the overall compression level.In this paper,we present various methods to improve the ratio of encodable patterns.These methods are b... 相似文献
3.
Dennis Heinson York Yannikos Frederik Franke Christian Winter Markus Schneider 《Datenschutz und Datensicherheit - DuD》2010,34(2):75-79
Der Einsatz von Informationstechnologie (IT) in Organisationen bietet viele M?glichkeiten des Missbrauchs. Besch?ftigte k?nnen
sich die besonderen Eigenschaften der IT zunutze machen, um sich etwa in gesch?ftssch?digender Weise Vorteile zu verschaffen.
Gleichzeitig erm?glicht IT aber auch, verbotene Handlungen aufzuspüren und zu belegen (IT-Forensik). Der Beitrag beschreibt
die technische Praxis von IT-forensischen Analysen und geht auf damit verbundene rechtliche Fragestellungen ein. 相似文献
4.
Two-stage quasi-class-E power amplifier in GaN HEMT technology 总被引:2,自引:0,他引:2
Gao S. Hongtao Xu Heikman S. Mishra U.K. York R.A. 《Microwave and Wireless Components Letters, IEEE》2006,16(1):28-30
This letter presents a two-stage quasi-class-E monolithic microwave integrated circuit power amplifier at 2.0GHz, which is based on field-plated GaN high electron mobility transistor technology. It consists of a driver stage and a power stage. The circuit schematic is described. The amplifier achieves an output power of 37.5dBm into a 50-/spl Omega/ load, a power added efficiency (PAE) of 50%, and a gain of 18.2dB. A power density of 5.6W/mm is achieved. 相似文献
5.
Wentao Wang José M. Herreros Athanasios Tsolakis Andrew P.E. York 《International Journal of Hydrogen Energy》2013
In this paper we show, for the first time, the feasibility of ammonia exhaust gas reforming as a strategy for hydrogen production used in transportation. The application of the reforming process and the impact of the product on diesel combustion and emissions were evaluated. The research was started with an initial study of ammonia autothermal reforming (NH3 – ATR) that combined selective oxidation of ammonia (into nitrogen and water) and ammonia thermal decomposition over a ruthenium catalyst using air as the oxygen source. The air was later replaced by real diesel engine exhaust gas to provide the oxygen needed for the exothermic reactions to raise the temperature and promote the NH3 decomposition. The main parameters varied in the reforming experiments are O2/NH3 ratios, NH3 concentration in feed gas and gas – hourly – space – velocity (GHSV). The O2/NH3 ratio and NH3 concentration were the key factors that dominated both the hydrogen production and the reforming process efficiencies: by applying an O2/NH3 ratio ranged from 0.04 to 0.175, 2.5–3.2 l/min of gaseous H2 production was achieved using a fixed NH3 feed flow of 3 l/min. The reforming reactor products at different concentrations (H2 and unconverted NH3) were then added into a diesel engine intake. The addition of considerably small amount of carbon – free reformate, i.e. represented by 5% of primary diesel replacement, reduced quite effectively the engine carbon emissions including CO2, CO and total hydrocarbons. 相似文献
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SC Langley GW Rickett A Hunt FJ Kelly AD Postle DA York 《Canadian Metallurgical Quarterly》1993,45(3):543-551
The biochemical maturation of the lung in late gestation and in the young animal is regulated by glucocorticoids. The present study was aimed at dissociating the different glucocorticoid receptor sites involved in these regulatory functions. The obese Zucker rat was selected as a model for this study as it exhibits hypersensitivity to glucocorticoid hormone action by virtue of its elevated receptor numbers and activity. Two synthetic steroid analogues were administered to obese animals; RU28362, a specific type II receptor agonist, and the type II antagonist RU486. RU28362 promoted a strong catabolic effect, which was associated with reduced food intake and the abolition of growth in the rats. The agonist, RU28362, attenuated developmental increases in antioxidant enzyme activities, and altered the growth of the tissue. At the age studied, development of the lung phosphatidylcholine (PC) system was almost complete, but RU28362 increased disaturated PC 16:0/16:0 concentrations by almost 2-fold, and altered the molecular composition of total pulmonary PC. RU486 attenuated the growth of the rats and reduced their food intake. Treatment with the type II antagonist attenuated lung growth and increased the activities of pulmonary copper zinc (Cu/Zn) and manganese (Mn) superoxide dismutases. RU486 had no effect on lung PC concentrations and molecular composition. The data suggest a role for type I glucocorticoid receptors in the regulation of the antioxidant enzyme system in the lung, as type II antagonism will channel endogenous glucocorticoid binding to the type I site. Type II receptor binding would appear to play a role in regulating the lung PC content. 相似文献
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