Thursday, July 21, 2016 3:00 pm
-
4:00 pm
EDT (GMT -04:00)
The Waterloo Institute for Nanotechnology (WIN) and the Department of Chemical Engineering present a Distinguished Lecture by Professor Jacob Israelachvili, in the Chemical Engineering Department of the University of California Santa Barbara (UCSB), United States.
Lecture: 3:00-4:00pm
Reception: 4:00-5:00pm
Adhesion, friction & lubrication of surfaces & liquid films and their relation to diverse phenomena such as how geckos climb on walls and ceilings, surface damage, and sensing
Abstract
Many
diverse
and
seemingly
unrelated
phenomena
at
the
macroscopic
level,
in
both
physical
and
biological
systems,
have
a
common
origin
at
the
microscopic
and
nanoscopic
(atomic
/
molecular)
levels.
This
talk
will
review
the
fundamental
aspects
of
adhesion,
stiction,
friction
(of
dry
and
liquid
lubricated
surfaces),
and
give
examples
of
everyday
processes
where
adhesion
and
friction
forces
act
simultaneously,
such
as
the
way
geckos
and
small
robots
climb
on
walls
and
ceilings.
It
is
also
becoming
increasingly
apparent
that
friction
forces
and
frictional
motions
are
rarely
constant
or
‘steady’,
but
proceed
in
intermittent
jumps,
commonly
referred
to
as
‘stick-slip’
sliding,
which
can
be
regular
(periodic)
or
irregular
(random
or
chaotic),
and
can
occur
at
the
nano,
micro,
and
macro-scales
(including
seismic
dimensions).
These
different
types
of
‘intermittent’
motions
are
central
to
earthquakes
and
to
many
biological
motions
and
sensory
perceptions,
including
how
blood
cells
move
along
capillary
walls
during
immune
recognition
processes,
food-texture
(mouth
feel),
and
other
types
of
tactile
perceptions.
Stiction
and
stick-slip
sliding
is
also
a
main
cause
of
damage
to
surfaces
and
biological
tissues.
I
will
also
describe
recent
and
ongoing
experiments,
mainly
using
the
Surface
Forces
Apparatus
(SFA),
for
measuring
these
forces.
Professor Jacob Israelachvili