Effect of Traveling Magnetic Field on Mould-Filling Length of the A357 Melt during Casting THin Walled Plate

In order to improver the mould filling ability ,the method for production of thin-walled castings in the traveling magnetic field was applied,The relationship between magnetic field density and input voltage as well as distance was investigated,and the mould filling length of A357 melt has been studied,The electromagnetic forces applied on the melt were also analyzed,The result shows that the mould-filling length of the melt increase rapidly with the increase of magnetic flux density,The mould filling lengths in gypsum upper mould and magnetic material upper mould were compared from the standpoint of application,It demonstrated that the steel upper mould is superior to gypsum mould.     

浅析新一代锂－离子电池充电器和电源适配器

新一代锂-离子电池的电解质、封装、尺寸、重量、能量密度及安全性能都有所改善，其充电器和电源适配器有些什么变化呢?     

从"视音频格式"开始说起

随着时代的进步,DVD、VCD、CD、MD、MP3等多媒体播出方式的不断涌现,以及网上流式技术的迅速普及,人们欣赏多媒体信息的方式也有了更多的     

陕西硅谷SGT-6A光纤识别器

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