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自有紫砂壶问世以来,深得文人之喜爱,不光把玩欣赏,还投入之中,原来妙在其中。难怪周高起在《阳羡茗壶系》中要有"一壶重不过数两,价重一二十金,能使土与黄金争价,世日趋华,抑足感矣"的感叹。更难怪清人汪文柏在赠给紫砂壶艺名家陈鸣远的《陶器行》的诗里,要呼喊"人间珠玉安足取,岂如阳羡溪头一丸土"了。 相似文献
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介绍了供配电系统节约电能的技术和方法,配电电压深入负荷中心、配电变压器的正确选择和经济运行、配电线路的合理选择和经济运行、电压调节和无功补偿等技术和方法的采用,对提高电能的利用率、节约电能、促进经济可持续发展和建设节约型社会具有重要的意义。 相似文献
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对聚丙烯纤维和钢纤维增强水泥砂浆复合材料和混凝土复合材料进行了MTS 准静态单轴压缩实验和压剪加载条件下的细观力学实验研究。比较两类纤维在这两种加载条件下的作用发现: 在单轴压缩条件下, 钢纤维作用显著, 聚丙烯纤维基本没有什么作用;在压剪加载条件下, 钢纤维在材料各个变形阶段均起明显作用, 聚丙烯纤维在加载过程中起到一定的作用, 但由于含量较少对材料的极限荷载基本没有贡献。在细观实验中, 观察到了钢纤维和碎石颗粒在材料破坏过程中脱粘与断裂的作用方式。但只是在水泥砂浆试件的局部观察到了孔洞崩塌现象, 对于其促成压缩带形成的机理尚须深入的工作。 相似文献
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Laser propulsion is a new concept technique of propulsion and will have important application in future space technology. There are two main driving types: the air-breathing mode and the rocket ablation mode. Vertical flight experiments have been carried out with a simple paraboloid type lightcraft in the air-breathing mode by TEA-C02 laser. In simulation a new model is used for LSD/LSC wave, the result shows that the momentum coupling coefficient increases with the increase of the pulse energy. 相似文献
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Based on the shear wave tracing(SWT) technique proposed by Tang Z P, particle velocity gauge and the dual internal measurement for pressure and shear waves (IMPS) system are applied to investigate the responses of fiber reinforced cement subjected to impact loading. Series of experiments are conducted. The results show that there exist four critical points, A, B, C, D, in p - V Hugoniot curves. They correspond to the Hugoniot elastic limit (I/EL) of the material, the critical point for shear strength limit and transition from damage state to failure state, void collapse, and solid compression, respectively. The critical point B is difficult to be aware of and never reported. However, it can be clearly disclosed with SWT method. Based on the analyses of shear strength, it can be concluded that the transversal wave, especially the unloading transversal wave, is especially important for the dynamic damage investigation of brittle materials. 相似文献
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