共查询到20条相似文献,搜索用时 46 毫秒
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none 《腐蚀工程科学与技术》2013,48(3):121-122
AbstractIn situ metallography has been used to study the effect of temperature on the microstructural changes on the outside surface of primary reformer tubes, used for the production of reformed gas suitable for ammonia synthesis in a 200 tonnes per day capacity ammonia plant. The outside skin temperature varied in the range of 860° to 1050°C. The studies indicated marked changes with increasing temperature in the size of grains and carbide morphology, i.e., the pattern and distribution of primary and secondary carbides. 相似文献
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Hans-Jürgen Engell 《工业材料与腐蚀》1988,39(10):285-286
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Leo F. Reinartz 《JOM Journal of the Minerals, Metals and Materials Society》1959,11(4):261-264
The history of steelmaking in the United States is a fascinating story of determination, sudden tragedy, exploitation, and inventive genius rolled into one gigantic plot. Mr. Reinartz’ flowing interpretation of the progress made in the last one hundred years is being presented in a series of four articles. 相似文献
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Leo F. Reinartz 《JOM Journal of the Minerals, Metals and Materials Society》1959,11(5):329-332
Part II of a four-part series on the history of steelmaking in the US, points out the inadequate safety and living conditions that existed in steel mills at the turn of the Century. Also defined are furnace and process developments. 相似文献
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Leo F. Reinartz 《JOM Journal of the Minerals, Metals and Materials Society》1959,11(7):444-448
This is the fourth and final installment of Leo Reinartz’ summation of the steelmaking industry over the first one hundred years. 相似文献
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Leo F. Reinartz 《JOM Journal of the Minerals, Metals and Materials Society》1959,11(6):403-406
Part III of a four-part series on the history of steelmaking in the US, describes furnace developments, improvements during the last few decades, and the contribution of the AIME. 相似文献
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W. Wiederholt 《工业材料与腐蚀》1971,22(3):280-280
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《Synthetic Metals》1988,24(4):379-389
Graphite fluorosulfates, CnSO3F, with n = 7 for stage-one materials, are ideally suited for 19F n.m.r. studies due to the unambiguous identity of the intercalate and its axially symmetric nature. The intensity of the signal shows a clear dependence on the orientation of the c axis with respect to the oscillating radio-frequency field H1. The chemical shift value, however, is affected by the orientation of the c axis with respect to H0. The powder spectrum of the stage-one material C7SO3F extends from 10 to 100 ppm at low temperatures, while motional narrowing at room temperature contributes to a sharp signal at the lower field end of the powder spectrum, corresponding to an axially symmetric chemical shift tensor. Angular dependence studies on C7SO3F samples made from HOPG indicate that the majority of the intercalated SO3F− ions are oriented with their molecular C3 symmetry axes parallel to the c axis of graphite, or normal to H0. Multi-staged samples made from HOPG demonstrate the stage dependence of the chemical shift of intercalated SO3F− ions. The chemical shift of the stage-one material is observed in the region of 10 – 12 ppm, while higher-staged materials show resonances at less shielded regions. 相似文献