With the expansion of frequency range of modern laser and the enrichment of light detection method, sensitivity of Raman spectrum has made great progress.
随着激光光源频率范围的不断扩展，光探测手段的不断丰富，拉曼光谱的检测灵敏度获得了极大的提高；
2
The application and effect of US Derrick overlapping high frequency vibrating fine screen in the transformation for capacity expansion of System 321 in Ekou Iron Concentrator are described.
介绍了美国德瑞克重叠式高频振动细筛在峨口铁矿选矿厂321系统扩能改造中的应用和效果。
3
Doppler effect causes not only carrier frequency offset, but also symbol expansion or compression for wideband acoustic communication signal.