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31.
To develop satisfactory alloys without Cr or Ni for high-temperature application up to 1100C, three alloys based on Fe-10%Al-Si with differing fourth (or fifth) element additions were oxidized in air at 1100°Cfor 24 hr. A low carbon, Fe-30Mn-10Al-Si alloy exhibited excellent high-temperature oxidation resistance. The total weight gain for 24 hr oxidation in air at 1100°C was only 1.03 mg/cm
2. After air oxidation for 6 days at 1100°C, no nodule formation or breakthrough oxidation occurred. Post-oxidation SEM and EDAX examination showed that a thin, compact, protective alumina scale formed on the alloy.Visiting Scientist (People's Republic of China). 相似文献
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An aerial distance sampling survey of double-crested cormorants (Phalacrocorax auritus) was conducted in the northern region of Lake Huron (North Channel; four largest lakes of Manitoulin Island; South Shore of Manitoulin Is. facing the main body of the lake) to assess the relative distribution, abundance and prey demand by cormorants on inland lake vs. coastal habitat. On a per area basis, the density (approx. 1-2 cormorants ? km− 2) and prey demand (approx. 1.2 kg ha− 1) of cormorants in the four inland lakes matched that of the North Channel. The South Shore had approximately half the density and prey demand as the other two areas. Cormorants on the inland lakes of Manitoulin Island represented 13% early in the season and a high of 33% of the total population for this region of Lake Huron later in the summer. Estimating regional distributions of cormorants within the Great Lakes basin is important because mapped nest colonies and nest counts are not representative of the actual distribution of foraging cormorants during and after the nesting season. There are two general conclusions to emerge from this survey. First, aquatic productivity from both Great Lakes coast and inland lakes contributes to trends in population and distribution of cormorants in the northern region of Lake Huron and perhaps elsewhere. Second, inland aquatic ecosystems are important throughout a season for foraging cormorants from the Great Lakes and may become more important as Great Lake productivity trends downward. 相似文献
35.
ISA100自动化用无线系统旨在统一工业无线技术。以下叙述了来自200多家公司的600名成员是如何合作实现这一目标的。 相似文献
36.
Mark T.Hoske 《软件》2008,(5):4
我非常钟爱办公用品商店的商业模式,就如同按下按钮那般简单。如果收益同按按钮一样简单,你能想象将会发生什么吗?现在就有这样一个例子:我们写(按钮),您接受(动),每个人都获取收益(这很简单)。标准其实就处于可盈利的按钮之间。我坚信ISA88第5部分标准的价值,如果可以得到广泛的应用,将意味着许多设施的盈 相似文献
37.
Summary The nature of the excited state interactions in poly(ethylene terephthalate) is still subject to debate. We study a new series of model compounds composed of a central terephthaloyl group condensed with -hydroxy--phenyl-n-alkanes. Although the molecular architecture prevents these molecules from achieving symmetric ring-ring overlap, the steady-state fluorescence spectra are remarkably similar to those of other models studied earlier, where such overlap was expected. The solvent polarity dependence suggests that the excited state complex is an exciplex and not an excimer. 相似文献
38.
Technical Physics Letters - Stabilization of a detonation wave in a stoichiometric hydrogen–air mixture flowing at a supersonic velocity into a plane symmetric channel with constriction has... 相似文献
39.
I. E. Strelnikova E. E. Grinberg Yu. I. Levin A. E. Amelina V. I. Rakhlin 《Inorganic Materials》2016,52(12):1250-1253
We have studied reactions of metallic magnesium with ethyl cellosolve and a mixture of ethyl cellosolve and tetraethyl orthosilicate and demonstrated the possibility of preparing a mixed magnesium–silicon cellosolvate that can be used as a precursor for the synthesis of forsterite and enstatite. 相似文献
40.