Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a...Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a code or some assumptions. In this paper, a diagnostic idea of using line-pairs emitted from a doubly-excited state is proposed. By using the method presented in this paper, Te and the fractional population ratio of bare nuclei and H-like ions are directly obtained from the emission intensity ratios.展开更多
The image features, such as enhancements, shadows and lateral shadows, posterior to a tumor in a B-Mode diagnostic ultrasonography, are studied. The tumor is simplified as a homogeneous cylinder in an inhomogeneous me...The image features, such as enhancements, shadows and lateral shadows, posterior to a tumor in a B-Mode diagnostic ultrasonography, are studied. The tumor is simplified as a homogeneous cylinder in an inhomogeneous medium. Using the ray theory we derive the intensity in the region behind the cylinder. Taking the influences of sound attenuation and the time gain compensation of the B-Mode displyer into acount , we simulate with a computer five images corresponding to our experiments conducted with a tissue equivalent phantom. The theoratical images seem to be in good qualitative agreement with the experimental results.展开更多
文摘Resonance lines are extensively used to diagnose electronic temperature Te and ions distribution. However, the analysis of the x-ray spectroscopy emitted from plasmas produced by a ns laser Jsually needs the help of a code or some assumptions. In this paper, a diagnostic idea of using line-pairs emitted from a doubly-excited state is proposed. By using the method presented in this paper, Te and the fractional population ratio of bare nuclei and H-like ions are directly obtained from the emission intensity ratios.
基金Supported by National Natural Science Fundation of China
文摘The image features, such as enhancements, shadows and lateral shadows, posterior to a tumor in a B-Mode diagnostic ultrasonography, are studied. The tumor is simplified as a homogeneous cylinder in an inhomogeneous medium. Using the ray theory we derive the intensity in the region behind the cylinder. Taking the influences of sound attenuation and the time gain compensation of the B-Mode displyer into acount , we simulate with a computer five images corresponding to our experiments conducted with a tissue equivalent phantom. The theoratical images seem to be in good qualitative agreement with the experimental results.
