The isotope shifts, hyperfine structure, spontaneous emission branch ratio of the first excited level and Doppler width of the atom vapor beam were measured using laser induced fluorescence.

采用原子蒸气束激光诱导荧光法测量钆原子的第一激发态的同位素位移及超精细结构、原子跃迁自发辐射的分支比和原子蒸气束的多普勒宽度。

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Fixing the spectrum width of the weather echo signals, we change theirs mean Doppler frequency and filter them using regression filter. After filtering, we analyze the attenuation of them.

在天气回波信号谱宽固定的情况下，通过改变天气回波信号的平均多普勒频率，分析了回归滤波器对它的衰减情况。

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Result: The color Doppler signals and flow width were all increased in normal lower limb arteries after the contrast agent was admitted.

结果：注射造影剂后下肢动脉彩色血流信号迅速增多、血流束增宽。

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