• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Ultrasonics, Ferroelectrics and Frequency Control, IEEE Transactions on >Subharmonic scattering of phospholipid-shell microbubbles at low acoustic pressure amplitudes
【24h】

Subharmonic scattering of phospholipid-shell microbubbles at low acoustic pressure amplitudes

机译：低声压振幅下磷脂壳微泡的次谐波散射

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Subharmonic scattering of phospholipid-shell microbubbles excited at relatively low acoustic pressure amplitudes (<30 kPa) has been associated with echo responses from compression-only bubbles having initial surface tension values close to zero. In this work, the relation between subharmonics and compression-only behavior of phospholipid-shell microbubbles was investigated, experimentally and by simulation, as a function of the initial surface tension by applying ambient overpressures of 0 and 180 mmHg. The microbubbles were excited using a 64-cycle transmit burst with a center frequency of 4 MHz and peak-negative pressure amplitudes ranging from 20 of 150 kPa. In these conditions, an increase in subharmonic response of 28.9 dB (P < 0.05) was measured at 50 kPa after applying an overpressure of 180 mmHg. Simulations using the Marmottant model, taking into account the effect of ambient overpressure on bubble size and initial surface tension, confirmed the relation between subharmonics observed in the pressure-time curves and compression-only behavior observed in the radius-time curves. The trend of an increase in subharmonic response as a function of ambient overpressure, i.e., as a function of the initial surface tension, was predicted by the model. Subharmonics present in the echo responses of phospholipid-shell microbubbles excited at low acoustic pressure amplitudes are indeed related to the echo responses from compression-only bubbles. The increase in subharmonics as a function of ambient overpressure may be exploited for improving methods for noninvasive pressure measurement in heart cavities or big vessels in the human body.
机译：在相对较低的声压幅度（<30 kPa）下激发的磷脂-壳微泡的亚谐波散射与来自初始表面张力值接近零的仅压缩泡的回声响应有关。在这项工作中，通过施加0和180 mmHg的环境超压，通过实验和模拟研究了次谐波与磷脂壳微气泡的仅压缩行为之间的关系，该关系是初始表面张力的函数。使用中心频率为4 MHz且峰值负压幅度范围为150 kPa的20的64周期发射脉冲激发微泡。在这些条件下，施加180 mmHg的超压后，在50 kPa处测得的次谐波响应增加了28.9 dB（P <0.05）。使用Marmottant模型进行的模拟考虑了环境超压对气泡尺寸和初始表面张力的影响，证实了在压力时间曲线中观察到的次谐波与在半径时间曲线中观察到的仅压缩行为之间的关系。该模型预测了次谐波响应随环境超压而增加的趋势，即随初始表面张力而变的趋势。在低声压振幅下激发的磷脂-壳微泡的回声响应中存在的亚谐波确实与仅压缩气泡的回声响应有关。作为环境超压的函数的次谐波的增加可用于改进用于人的心腔或大血管中的无创压力测量的方法。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号