کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8130326 1523200 2016 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The lifetime evaluation of vapourised phase-change nano-droplets
ترجمه فارسی عنوان
ارزیابی طول عمر ناپایدارهای ناپیوسته تغییر فاز
کلمات کلیدی
نانو قطره تغییر فاز، تبخیر قطره آکوستیک، فلوئوروکربن، تصفیه کننده، تصویربرداری با سرعت بالا، طول عمر حباب،
موضوعات مرتبط
مهندسی و علوم پایه فیزیک و نجوم آکوستیک و فرا صوت
چکیده انگلیسی
Phase-change nano-droplets (PCNDs) are sub-micron particles that are coated with phospholipid and contain liquid-state perfluorocarbons such as perfluoropentane (boiling point = 29 °C) and perfluorohexane (boiling point = 57 °C), which can vapourise upon application of ultrasound. The bubbles generated by such reactions can serve as ultrasound contrast agents or HIFU sensitisers. However, the lifetime of bubbles generated from PCNDs on μs-order is not well known. Knowledge of the condition of PCND-derived bubbles on μs-order is essential for producing bubbles customised for specific purposes. In this study, we use an optical measurement system to measure the vapourisation and stability of the bubbles (bubble-lifetime) as well as the stability-controlling method of the nucleated bubbles on μs-order while changing the internal composition of PCNDs and the ambient temperature. PCND-derived bubbles remain in a bubble state when the boiling point of the internal composition is lower than the ambient temperature, but lose their optical contrast after approximately 10 μs by re-condensation or dissolution when the boiling point of the internal composition is higher than the ambient temperature. We reveal that the superheating condition significantly affects the fate of vapourised PCNDs and that the bubble-lifetime can be controlled by changing both the ambient temperature conditions and the internal composition of PCNDs.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ultrasonics - Volume 69, July 2016, Pages 97-105
نویسندگان
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