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CSS(Cascading Style Sheets)它是一种制作网页的新技术.与传统的html语言相比,CSS技术为网页设计提供了更丰富、更美观的表现方式.结合几个实例详细介绍如何利用CSS来美化网页表格,使得网页增光添彩,从而能够吸引更多的浏览者. 相似文献
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青藏高原冻土地区输电线路电力杆塔基础设计 总被引:2,自引:0,他引:2
通过分析多年冻土对电力杆塔基础的受力特点,并经过理论计算及对非冻土地区和冻土地区电力杆塔基础设置的比较,论述了青藏高原多年冻土地区电力输电线路杆塔基础设计的特殊性和必要性,为冻土地区输电线路杆塔基础设置提供了新的技术和方法. 相似文献
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In 2013, over 500 million metric tons of Iron Ore Fines (IOF) were transported around the world using bulk carriers. Under certain conditions IOF, while being transported, can possibly undergo liquefaction. Since 2006, there has been eight reported bulk carrier casualties possibly caused by the liquefaction of IOF. The objective of this study is to evaluate, compare and verify the limitations and relevance of the Proctor/Fagerberg, Flow Table and Penetration test methods that are used to determine the Transportable Moisture Limit (TML) of IOF. The TML is the maximum gross water content that bulk cargoes, including IOF, may contain while being transported at sea without being at risk of liquefying. A thorough literature review, along with laboratory research, was carried out to compare the TML results from the three leading test methods to determine whether they produce reliable results when testing IOF. The study concludes that the three test methods, as stated in the 2012 International Maritime Solid Bulk Cargoes Code, are unverified and therefore not appropriate for testing IOF. This is due to the variation in the results produced by the three test methods and also due to the difference in the physical properties of IOF when compared with the materials that were originally intended for testing. It is noted that the TML alone may not control the potential liquefaction of IOF and further studies, regarding the physical properties and system variables, which cause the material to liquefy, are required to determine the liquefaction potential of IOF. 相似文献
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非赫兹接触轮轨蠕滑力数表TPLR的研究 总被引:4,自引:1,他引:4
本文介绍了直线轨道上单轮对运动状态蠕滑率和蠕滑力关系律数表的编制方法。数表中轮轨蠕滑率/力计算模型是非赫兹型的。 相似文献