Colloquium
Series
Sushanta
Mitra
Executive
Director
of
the
Waterloo
Institute
for
Nanotechnology
Mechanical
and
Mechatronics
Engineering
and
Department
of
Physics
&
Astronomy
University
of
Waterloo
Dr.
Mitra's research
interests
are
in
the
fundamental
understanding
of
fluid
transport
in
micro
and
nano-scale
confinements
with
applications
in
energy,
water,
and
bio-systems.
For
his
contributions
in
engineering
and
sciences,
he
has
been
elected
as
the
Fellow
of
the
American
Society
of
Mechanical
Engineers
(ASME),
the
Canadian
Society
for
Mechanical
Engineering
(CSME),
the
Engineering
Institute
of
Canada
(EIC),
the
Canadian
Academy
for
Engineering
(CAE),
the
Indian
National
Academy
of
Engineering
(INAE
–
Foreign
Fellow),
the
Royal
Society
of
Chemistry
(RSC,
UK),
the
American
Physical
Society
(APS),
and
the
American
Association
for
the
Advancement
of
Science
(AAAS).
He
is
also
a
Fellow
of
the
National
Institute
for
Nanotechnology
(NINT)
and
the
recipient
of
2015
Engineering
Excellence
Medal
from
the
Ontario
Society
of
Professional
Engineers.
Refreshments
in
PHY
313
starting
at
3:30
pm
Abstract
Capillary
forces
play
a
significant
role
in
number
of
practical
applications
related
to
microfluidic
devices
for
detection
of
biomolecules,
mixing
of
analytes
and
transport
of
fluid.
Through
first
principle
analysis,
we
have
demonstrated
that
different
regimes
for
capillary
flow
exist,
both
for
horizontal
and
vertical
capillaries.
We
have
further
performed
in-depth
studies
to
understand
the
role
of
the
electric
double
layer
in
fluid
transport
in
narrow
confinements.
In
parallel,
wetting
characteristics
of
a
given
substrate
is
of
paramount
importance
in
material
science
to
characterize
hydrophilic/
hydrophobic
nature
of
the
synthesized
materials.
We
have
developed
a
new
method
which
allows
us
to
characterize
(measure
contact
angle)
any
substrate
(superhydrophobic/
superoleophobic)
using
needle-free
drop
deposition
technique,
where
the
characterizing
substrate
can
be
kept
either
in
air
or
submerged
within
a
given
liquid.
We
have
also
derived
a
new
lubrication
equation
to
characterize
the
coalescence
behavior
of
two
drops
on
under-liquid
substrates.
Using
this
technique
of
drop
deposition,
under-water
superoleophobicity
of
glass
surfaces
and
fish
scales
are
characterized.
Finally,
some
new
results
will
be
shared
on
development
towards
self-healing
superhydrophobic
surfaces
in
air
and
oleophobic
surfaces
in
under-water.
Sushanta
Mitra