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3D hierarchical flowerlike WS2 microspheres were synthesized through a facile one-pot hydrothermal route.The as-synthesized samples were characterized by powder X-ray powder diffraction (XRD),energy-dispersive spectroscopy (EDS),scanning electron microscopy (SEM) and Raman.SEM images of the samples reveal that the hierarchical flowerlike WS2 microspheres with diameters of about 3-5μm are composed of a number of curled nanosheets.Electrochemical tests such as charge/discharg... 相似文献
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随身听由于采用超薄型电机,有时会出现时停时转或时快时慢的现象,特别是更换新电机时,往往感觉走带速度与以往似有不同。业余爱好者却又没有专业的测速装置进行检测,为此笔者介绍一个行之有效的检测方法。准备一盒磁带、一只钟(或表)和一把卷尺。将磁带“快退”或“快进”至磁带开始处,按下“播放”键的同时开始用钟(或表)计时,播放至60秒时按“停止”键,取出磁带,从带盒上的磁头槽中抽出刚播放过的磁带至抽不动,用卷尺测量出这一段磁带的长度。正常的走带速度是4.76cm/s,若其长度为4.76cm/s×60s=285.6cm,则最标准。实验表明,长度误差3%基本听不出差别,即277~294cm都为带速正常。 相似文献
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