D_4J-88调度监督系统在露天矿铁路运输中的应用

介绍了D4J-88调度监督系统的功能特点,论述了该系统在露天煤矿铁路运输中的应用,并分析了其在露天煤矿生产中的作用。     

Co^3＋—modified Surface of LiMn2O4 Spinel for its Improvementof Electrochemical Properties

Cobalt was used to modify the surface of spinel LiMn2O4 by a solution technique to produce Co^3 -modified surface material (COMSM). Cobalt was only doped into the surface of LiMn2O4 spinel. XPS(X-ray photoelectron spectroscopy) analysis confirms the valence state of Co^3 . COMSM has stable spinel structure and can prevent active materials from the corrosion of electrolyte. The ICP(inductively coupled plasma) determination of the spinel dissolution in electrolyte showed the content of Mn dissolved from COMSM was smaller than that from the pure spinel. AC impedance patterns show that the charge-transfer resistance (Rct) for COMSM is smaller than that for pure spinel. The particles of COMSM are bigger in size than those of pure spinel according to the micrographs of SEM(scanning electron microscopy). The determinations of the electrochemical characterization show that COMSM has both good cycling performance and high initial capacity of 124.1 mA/h at an average capacity loss of 0.19 mAh/g per cycle.     

JVC XA—F57／XA—F107

JVC推出的这两款全新闪存播放器最大的特色就是拥有独特的造型和多彩的外观。其中。XA-F57有乳白色．粉红色和银白色三种，而XA—F107有浅灰色、纯黑色和粉红色可以选择。两款MP3播放器都支持MP3．WMA和WMA-DRM格式的音乐播放。有5种音效模式和1种用户自定义模式。它们都支持音频直录功能．可将CD、收音机磁带等模拟音源转变成MP3文件。XA--F57和XA-F107的容量分别为512MB和1GB，并且都配备了MM喜欢的项链式耳塞。其中．XA—F57价格为99美元，XA-F107售价则为149美元。     

锦鸟也歌唱ViewSonic P20 MP3播放器

ViewSonic P20系列MP3播放器有两款，分别是1GB容量的P204和512MB容量的P203，我们所使用的是P203。     

和黄3G之路

当前，我国对3G的讨论达到白热化，标准之争、牌照之争彼此起伏，让我们看到这个还没有到来的时代充满了硝烟。我国在3G道路上的发展步伐慢了许多。虽然我们一直期望通过3G赶超世界先进的通信技术，但是又不得不承认，想要做到这一点还存在一定的困难。