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Title: Nucleation dynamics around single microabsorbers in water heated by nanosecond laser irradiation

Abstract

Suspensions containing micro- and nanoabsorbers, which are irradiated by short laser pulses, are used for a manifold of procedures in medicine, biotechnology, and other fields. Detailed knowledge of the bubble nucleation and dynamics, which is induced by the heat transfer from the absorber to the surrounding transparent water, is essential for understanding the underlying processes occurring on a microscopic scale. We investigated the rapid phase change phenomena including temperature, heating rates, pressure generation, bubble nucleation, and initial bubble growth around absorbing micron-sized melanin particles (retinal pigment epithelial melanosomes) during irradiation with 12 ns (full width at half maximum) laser pulses at a wavelength of 532 nm. The melanosomes were heated at rates in the order of 10{sup 10} K/s. A mean bubble nucleation temperature of 136 deg. C was found. The initial bubble expansion was observed by time-resolved microscopy. The expansion velocities range from 10 m/s at 1.5-fold to 85 m/s at 8.5-fold threshold radiant exposure for bubble formation, respectively. The expansion velocity increases in the investigated range almost linearly with the applied radiant exposure.

Authors:
;  [1]
  1. Medizinisches Laserzentrum Luebeck GmbH, Peter-Monnik-Weg 4, D-23562 Luebeck (Germany)
Publication Date:
OSTI Identifier:
20979423
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 11; Other Information: DOI: 10.1063/1.2740348; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BIOTECHNOLOGY; BUBBLE GROWTH; BUBBLES; EXPANSION; HEAT TRANSFER; HEATING RATE; IRRADIATION; LASER RADIATION; LASERS; MEDICINE; MELANIN; MICROSCOPY; NUCLEATION; PARTICLES; PULSES; RHODOPSIN; SPECTRA; SUSPENSIONS; TIME RESOLUTION; WATER

Citation Formats

Neumann, Joerg, and Brinkmann, Ralf. Nucleation dynamics around single microabsorbers in water heated by nanosecond laser irradiation. United States: N. p., 2007. Web. doi:10.1063/1.2740348.
Neumann, Joerg, & Brinkmann, Ralf. Nucleation dynamics around single microabsorbers in water heated by nanosecond laser irradiation. United States. doi:10.1063/1.2740348.
Neumann, Joerg, and Brinkmann, Ralf. Fri . "Nucleation dynamics around single microabsorbers in water heated by nanosecond laser irradiation". United States. doi:10.1063/1.2740348.
@article{osti_20979423,
title = {Nucleation dynamics around single microabsorbers in water heated by nanosecond laser irradiation},
author = {Neumann, Joerg and Brinkmann, Ralf},
abstractNote = {Suspensions containing micro- and nanoabsorbers, which are irradiated by short laser pulses, are used for a manifold of procedures in medicine, biotechnology, and other fields. Detailed knowledge of the bubble nucleation and dynamics, which is induced by the heat transfer from the absorber to the surrounding transparent water, is essential for understanding the underlying processes occurring on a microscopic scale. We investigated the rapid phase change phenomena including temperature, heating rates, pressure generation, bubble nucleation, and initial bubble growth around absorbing micron-sized melanin particles (retinal pigment epithelial melanosomes) during irradiation with 12 ns (full width at half maximum) laser pulses at a wavelength of 532 nm. The melanosomes were heated at rates in the order of 10{sup 10} K/s. A mean bubble nucleation temperature of 136 deg. C was found. The initial bubble expansion was observed by time-resolved microscopy. The expansion velocities range from 10 m/s at 1.5-fold to 85 m/s at 8.5-fold threshold radiant exposure for bubble formation, respectively. The expansion velocity increases in the investigated range almost linearly with the applied radiant exposure.},
doi = {10.1063/1.2740348},
journal = {Journal of Applied Physics},
number = 11,
volume = 101,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}
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