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111.
尽管连续铸钢技术已经在全世界广泛、成功地应用,然而通过现存所选择的工艺和设计参数来生产高质量产品还有一些障碍。近年来,通过冶金工作者的不断努力,取得了一些突破性成就。 相似文献
112.
A refined beam theory based on the refined plate theory 总被引:5,自引:0,他引:5
Summary Based on the refined plate theory, a refined theory of rectangular beams is derived by using the Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. The solutions based on the new theory are the same as the exact solutions of elasticity theory. In three examples it is shown that the new theory provides as good or better results than Levinson’s beam theory when compared to those obtained from the linear theory of elasticity. 相似文献
113.
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115.
Ni/Co bimetallic nano-cluters have been prepared from the aqueous solution by reducing their corresponding metal salts under suitable conditions. The experimental conditions including the type and concentration of protective agent, feeding order and the pH of the solution that influence the average particle size have been studied in detail. Transmission electron microscopy (TEM) indicates that the shape of those bimetallic nano-cluster particles is spheroid. The alloy structure has been shown by X-ray powder diffraction (XRD). The X-ray photoelectron spectroscopic (XPS) data have confirmed that the nickel and cobalt in the bimetallic nano-clusters are in the zero-valence state. 相似文献
116.
117.
Z. F. Li J. Liu J. J. Liu J. Gao S. Pirzada C. Y. Chen P. Cheng 《Microsystem Technologies》2003,9(5):375-378
By changing the head's Z-height, a new accelerated drag test has been developed to characterize head wear under high interference conditions. Compared
to contact start stop (CSS) and other drag tests, heads wear faster in our approach, due to the stressed condition at the
tilted trailing edge. The optimized Z-height has been chosen so that the head-disk interference and acoustic emission are maximized. The wear volume can be estimated
by optical microscopy. The influence of lube bonded ratio and X1P additive amount on head wear has been studied for AM3001
lubricant. Lower bonded ratio and higher X1P additive were found to give rise to less head wear, which is in agreement with
the existing results of contact start-stop and other drag tests. In media manufacturing, tape burnish processes were found
to significantly affect the bonded ratio in the AM3001/X1P lubricant system, which consequently affects head wear. Short tape
burnish times were found to reduce the media's head wear.
Received: 16 July 2002/Accepted: 23 October 2002
The authors would like to thank Dr. Ken E. Johnson for his extensive support in this project.
Paper presented at the 13th Annual Symposium on Information Storage and Processing Systems, Santa Clara, CA, USA, 17–18 June,
2002 相似文献
118.
The degradation of benzidine in aqueous solution by the low temperature plasma was examined. The results showed that the concentration of medium and the value of pH have an appreciable effect on the degradation of benzidine. What is more important is that iron ions acting as a catalyst play an important role in this reaction. For exploring the degradation mechanism of benzidine, some of the intermediate products were recorded by HPLC (high performance liquid chromatography). 相似文献
119.
120.
锝的TBP萃取化学行为研究 总被引:2,自引:0,他引:2
报道了在硝酸体系中用30%TBP-正十二烷萃取Tc(Ⅶ)的实验结果。详细研究了硝酸、硝酸铀酰、硝酸铀(Ⅳ)、硝酸铵、亚硝酸钠、硝酸锆、硝酸钚、硝酸铈,亚硝酰钌、硝酸羟胺、硝酸肼浓度及温度、相比等因素对Tc(Ⅶ)萃取化学行为的影响。实验结果表明,在不含铀的硝酸体系中,硝酸、硝酸铵、硝酸钚、硝酸锆、硝酸铈、亚硝酸酰钌浓度及萃取温度对Tc(Ⅶ)的分配比影响很大,而亚硝酸钠、硝酸肼及硝酸羟胺浓度对Tc(Ⅶ)的分配比影响较小;在含铀的硝酸体系中,硝酸浓度对Tc(Ⅶ)的分配比有影响,而萃取温度、硝酸钚、锆的影响较小。Tc(Ⅶ)在含或不含铀的硝酸体系中,与TBP分别形成UO2NO3·TcO4·2TBP和HTcO4·3TBP萃合物。 相似文献