% IMPORTANT: The following is UTF-8 encoded. This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.
@INPROCEEDINGS{Lang:849730,
author = {Lang, Peter R. and Liu, Yi and De Sio, Silvia and Dhont,
Jan K.G.},
title = {{P}article {W}all {I}nteractions and {N}ear-{W}all
{D}ynamics of {C}olloidal {S}pheres in {C}rowded
{E}nvironments},
reportid = {FZJ-2018-03862},
year = {2018},
abstract = {Over the last decade we developed instrumental equipment,
based on evanescent wave light scattering, to investigate
the static interaction of colloidal particles with an
adjacent wall, as well as the near wall dynamics of these
particles. In this presentation, I will give an introduction
to the techniques, before discussing several
experiments.Using Total internal Reflection Microscopy
(TIRM), we investigated the depletion interaction between a
colloidal probe sphere and a flat wall, induced by rod–
and disc– shaped particles at rest [1,2] and under the
influence of flow fields. There we could show that the
strength of these depletion potentials can be tuned by the
applied shear rate [2].Further we studied the near wall
dynamics of a single probe sphere in a crowded environment
of rods by TIRM. The standard approach extract dynamic
information from TIRM data is extracting the probe
particle’s diffusion coefficient normal to the wall from
the mean square displacement (MSD) vs. time curves. However,
in the course of our investigation we discovered that it is
more reliable to determine the particle’s drift velocity
from the mean displacement (MD) vs. time curves [3,4]. Using
Evanescent Wave Dynamic Light Scattering (EWDLS) we studied
the near-wall dynamics of spherical particles as a function
of concentration, providing experimental prove for the long
standing theoretical prediction that particle dynamics near
walls are slowed down and are anisotropic [5]. Upon
increasing particle concentration the slowing down is
diminished, where the diminishment is again different in the
directions parallel and normal to the interface
[6].References[1] C. July, D. Kleshchanok, P. R. Lang Eur.
Phys. J. E 35, 60 (2012). DOI 10.1140 epje/i2012-12060-7[2]
S. De Sio and P. R. Lang, Z. Phys. Chem. 229, 1161
(2015).[3] S. Desio, PhD-Thesis Heinrich-Heine-Universitaet
Duesseldorf, Germany[4] S. De Sio, Y. Liu, J.K.G. Dhont and
P. R. Lang manuscript in preparation[5] P. Holmqvist, J. K.
G. Dhont, P. R. Lang J. Chem. Phys. 126, 044707 (2007).[6]
Y. Liu et al. Soft Matter 11, 7316 (2015).},
month = {Jun},
date = {2018-06-18},
organization = {30th International Conference on
Science and Technology of Complex
Fluids, San Luis Potosí (Mexico), 18
Jun 2018 - 22 Jun 2018},
subtyp = {Invited},
cin = {ICS-3},
cid = {I:(DE-Juel1)ICS-3-20110106},
pnm = {551 - Functional Macromolecules and Complexes (POF3-551) /
ESMI - European Soft Matter Infrastructure (262348) /
SOMATAI - Soft Matter at Aqueous Interfaces (316866) / EUSMI
- European infrastructure for spectroscopy, scattering and
imaging of soft matteer (731019)},
pid = {G:(DE-HGF)POF3-551 / G:(EU-Grant)262348 /
G:(EU-Grant)316866 / G:(EU-Grant)731019},
typ = {PUB:(DE-HGF)6},
url = {https://juser.fz-juelich.de/record/849730},
}