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1.
Amanda Alliband Daniel W. Lenz Laura E. Stevenson Travis Whitmer Rex Cash Dennis Burns Sarah Hall William T.K. Stevenson 《Progress in Organic Coatings》2008
A model has been proposed to explain the failure of the original BMS10-39 epoxy paint on upper vertical surfaces in B-52 fuel tanks. The model involves interaction of the paint with DIEGME, a fuel system ice inhibitor (FSII) in jet fuel, that is distilled from the liquid fuel. In this communication, distillation experiments used to support the model are refined to better match the mass transfer of vapor from fuel in a B-52 fuel tank at close to room temperature. The interaction of these lower temperature distillates with the paint affirms the earlier model. On the basis of these experiments it is proposed that paint failure may be controlled or eliminated by reducing the level of DIEGME in the fuel. Proposed changes in military jet fuel composition are detailed. 相似文献
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Einstein Gilles O.; McDaniel Mark A.; Richardson Sarah L.; Guynn Melissa J.; Cunfer Allison R. 《Canadian Metallurgical Quarterly》1995,21(4):996
Past research has frequently failed to find age differences in prospective memory. This article tested the possibility that age differences would be more likely to emerge on a prospective memory task that was high in self-initiated retrieval. In the 1st experiment, participants were asked to perform an action every 10 min (a time-based task presumed to be high in self-initiated retrieval); in the 2nd experiment, participants were asked to perform an action whenever a particular word was presented (an event-based task presumed to be relatively low in self-initiated retrieval). Age differences were found with the time-based task but not with the event-based task. This pattern of age differences was again found in a 3rd experiment in which a new experimental procedure was used and the nature of the prospective memory task was directly varied. Generally, the results suggest that self-initiated retrieval processes are an important component of age-related differences across both retrospective and prospective memory tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Jean-Marie Degroodt Brigitte Wyhowski de Bukanski Sarah Srebrnik 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1992,195(6):566-568
Summary A method combining immunoaffmity-chromatography (IAC) and high-performance liquid chromatography (HPLC) for the analysis of Salbutamol in liver with a low quantification limit of 1 g/kg has been developed. Salbutamol was extracted with 0.01 mol/L HCl and purified by IAC. The samples were analysed on a liquid Chromatograph fitted with a C18 -Bondapak column. A fluorometer was used for the detection of salbutamol. Recoveries of 67–80% could be obtained.
Immunoaffinitätschromatographische Reinigung von Salbutamol in Leber und Rückstandsbestimmung mittels HPLC und fluorimetrischer Detektion
Zusammenfassung Eine Methode, die Immunoaffinitäts-und Hochleistungsflüssigchromatographie verbindet, ist für die Analyse von Salbutamol in Leber entwickelt worden. Eine niedrige Bestimmungsgrenze von 1 g/kg Leber wurde erreicht. Salbutamol wurde mit 0,01 mol/L Salzsäure freigesetzt und durch Immunoaffinitätschromatographie gereinigt. Die Proben wurden durch Flüssigchromatographie auf einer C18 -Bondapak-Säule analysiert. Ein Fluorimeter wurde für die Detektion von Salbutamol benutzt. Ausbeuten von 67 bis 80% konnten erreicht werden.相似文献
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The last decade has placed the superiority of graphical user interfaces over traditional text-based approaches beyond dispute. In almost all contexts, users have found graphical interfaces easier to learn, faster to use, and less error-prone. However, it has been shown that the creation of powerful graphical interfaces takes up to 80% of the time required to develop an application. In our work, we seek to extend the benefits of graphical interaction to the next layer of computer user—the interface designer. Our work in this area is distinguished from other efforts by two important differences. First, while other efforts focus primarily on the design of standard user interfaces, our approach emphasizes the creation of unique and innovative interfaces by supporting, among other things, arbitrary user-designed graphical representations, direct specification of animation, and digitized sound. Second, our goal is to cater to the nonprogrammer. Thus, we address a challenging trade-off: maximizing power and flexibility in an extremely simple environment. We explore the utility of the prototype object-oriented paradigm, a high-level userinterface language, and a direct-manipulation programming environment in this context. 相似文献
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Using a novel sorption technique, the diffusion of some series of solutes in polyacrylamide gels has been investigated with regard to: (a) molecular size of solute; (b) concentration of solute and gel polymer; and (c) temperature. The approach used also yields the partition coefficient pertaining to sorption equilibrium. The ratio, , where Do refers to diffusion in the pure solvent, is found to reflect in part the characteristic interactions between solute and gel polymer. The temperature results indicate that the apparent activation energy for solute diffusion is approximately independent of the polymeric component for dilute gels. 相似文献
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Analysis of the hornet’s hemolymph revealed the presence of C16 and C18 fatty acids (70%), which were accompanied by minor quantities (ranging from 0.1% to 0.6%) of the following acids: C10∶0, C11∶0, C12∶0, C13∶0, C14∶0, C15∶0, C16∶0, and C17∶0. The hemolymph of the queen larvae contained more C18∶1 than the hemolymph of the worker larvae, and the percentage of C16∶1 was higher in the fat body and the midgut than in the hemolymph. The significance of these results is discussed. 相似文献
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Journal of Automated Reasoning - We investigate the proof complexity of modal resolution systems developed by Nalon and Dixon (J Algorithms 62(3–4):117–134, 2007) and Nalon et al. (in:... 相似文献
10.
Sarah Gordon 《Network Security》2004,2004(6):17-18
Antivirus software tests are important when selecting antivirus software. However, there are many different tests, and interpreting the results can be challenging. Additionally, the needs of the corporate customer and home user differ, and it is important to understand these differences in order to evaluate antivirus software tests critically. 相似文献