Physics of Fluids,
Год журнала:
2024,
Номер
36(11)
Опубликована: Ноя. 1, 2024
In
this
study,
we
provide
the
first
experimental
evidence
that
colloidal
hydrophilic
magnetite
nanoparticles
can
penetrate
through
bilayer
lipid
membrane
in
a
non-uniform
stationary
magnetic
field.
Hydrophilic
ligand-free
cationic
with
an
average
diameter
of
4
nm
were
added
to
surrounding
aqueous
solution
on
one
side
azolectin
membrane.
An
external
field
ensured
attraction
superparamagnetic
membrane,
resulting
formation
near-membrane
charged
layer
initial
polarization
As
result
passage
decreases,
and
becomes
depolarized.
Independent
methods
used
detect
passed
including
transmission
electron
microscopy
energy-dispersive
x-ray
spectroscopy.
The
discovered
effect
may
be
due
following
factors
interactions
nanoparticles.
Interaction
inhomogeneous
provides
localization
surface.
Collective
between
nanoparticles,
as
well
their
electric
fields,
lead
nanoparticle
aggregates.
matrix
leads
organic–inorganic
complexes
which
polar
surface
is
enveloped
by
layer.
penetration
caused
interaction
aggregates
local
intramembrane
fields.
The
challenges
of
constraints
and
imprecision
in
chemical
analysis
medical
diagnosis
are
particularly
evident
the
separation
blood
cells.
Pinched
flow
fractionation,
a
passive
microfluidic
technique,
has
gained
attention
for
its
potential
size-based
cell
separation.
Enhancing
efficiency
is
crucial,
especially
through
integration
with
external
forces
or
active
methods.
This
study
explores
use
dielectrophoresis
(DEP)
magnetophoresis
(MP)
to
separate
platelet
cells,
red
white
circulating
tumor
These
were
analyzed
both
independently
simultaneously.
To
achieve
optimal
separation,
Navier–Stokes
equations,
Newton's
second
law,
system's
electric
magnetic
fields
modeled.
Experiments
conducted
branched
microchannel
assess
impact
various
parameters,
including
buffer
rate,
pinched
section
width,
applied
voltage,
field
frequency,
intensity.
revealed
approximately
99%
under
conditions
Wp=20
μm,
Q2=1250
μl/h,
f=100
kHz,
V=3
V,
M=1.5
T.
findings
demonstrate
that
while
DEP
MP
individually
enhance
their
simultaneous
application
significantly
improves
precision,
achieving
complete
optimized
system
holds
great
promise
applications
analytical
chemistry
diagnostics,
analysis.
This
study
explores
electroosmotic
mixing
in
microfluidic
channel
with
predefined
surface
topology,
mainly
focusing
the
effect
of
charge-dependent
slip
length
on
underlying
dynamics.
Our
analysis
addresses
need
for
precise
control
flow
and
participating
fluids
at
microscale,
crucial
medical
biomedical
applications.
In
present
work,
we
consider
a
wavy
microchannel
non-uniform
charge
to
explore
behavior.
To
this
end,
adopting
finite-element
approach,
numerically
solve
Laplace,
Poisson–Boltzmann,
convection–diffusion,
Navier–Stokes
equations
steady-state.
The
model
is
validated
by
comparing
results
available
theoretical
experimental
data.
Through
numerical
simulations,
analyzes
patterns
microchannels,
highlighting
impact
lengths
efficiency.
For
example,
diffusive
Peclet
number
200,
efficiency
drops
from
95.5%
91.5%
when
considering
length.
It
established
that
fluid
rheology,
characterized
Carreau
behavior
index,
non-trivially
influences
field
modulation
Increased
numbers
enhance
velocity,
affecting
overall
constituent
chosen
fluidic
pathway.
instance,
increasing
0.01
1.0,
discernible
trend
emerges
higher
line
density
accelerated
velocity
within
microchannel.
also
examines
efficiency,
particularly
convective
regime
transport.
These
insights
offer
practical
guidance
designing
systems
intended
enhanced
capabilities.
Additionally,
likelihood
particle
aggregation
under
shear
forces,
vital
biological
non-Newtonian
fluids,
implications
drug
delivery,
diagnostics,
technologies.
Industrial & Engineering Chemistry Research,
Год журнала:
2024,
Номер
63(24), С. 10812 - 10824
Опубликована: Июнь 4, 2024
With
the
rapid
progress
in
micro/nanofluidics,
understanding
fundamental
mechanisms
of
ionic
transport,
fluid
behavior,
and
microsystem
dynamics
is
more
crucial
than
ever.
Given
substantial
expenses
associated
with
manufacturing
such
systems,
computational
simulations
offer
a
cost-effective
avenue
for
advancing
this
industry
sector
while
minimizing
financial
burdens.
In
context,
current
study
explores
impact
electrolyte
characteristics
by
numerically
analyzing
electroosmotic
flow
(EOF)
conical
nanochannel
featuring
charged
slippery
surfaces
coated
polyelectrolyte
layer.
Two
types
electrolytic
fluids,
namely,
water
(representing
Newtonian
fluid)
blood
plasma
non-Newtonian
fluid),
were
investigated.
The
behavior
electrolytes
was
modeled
using
Bingham–Papanastasiou
model.
governing
equations
nonlinear
model,
Poisson–Nernst–Planck
Navier–Stokes
equations,
solved
finite
element
method.
Various
parameters
including
slip
length,
surface
charge
density,
soft
layer
concentration
systematically
adjusted
to
assess
three
key
aspects:
EOF,
selectivity,
rectification.
findings
revealed
that
increasing
length
significantly
enhanced
EOF
both
electrolytes.
For
instance,
platelets
within
core
increased
1.5
times
extension
from
0
10
nm.
Additionally,
applying
positive
voltage
amplified
particularly
when
wall
charges
similar.
example,
decreasing
density
−0.02
C/m2
led
1.5-fold
increase
platelet
rising
0.028
0.042
m/s.
Scientific Reports,
Год журнала:
2024,
Номер
14(1)
Опубликована: Авг. 8, 2024
Abstract
The
PNP
nanotransistor,
consisting
of
emitter,
base,
and
collector
regions,
exhibits
distinct
behavior
based
on
surface
charge
densities
various
electrolyte
concentrations.
In
this
study,
we
investigated
the
impact
density
ion
transport
within
nanotransistors
at
different
concentrations
applied
voltages.
We
employed
a
finite-element
method
to
obtain
steady-state
solutions
for
Poisson–Nernst-Planck
Navier–Stokes
equations.
ions
form
depletion
region,
influencing
ionic
current,
analyze
influence
depth
region.
Our
findings
demonstrate
that
an
increase
in
results
deeper
zone,
leading
reduction
current.
However,
very
low
concentrations,
optimal
causes
current
reach
its
lowest
value,
subsequently
increasing
with
further
increments
density.
As
such,
$${V}_{app}=+1
\text{V}$$
Vapp=+1V
$${C}_{0}=1
\text{mM}$$
C0mM
,
increases
by
25%
when
rises
from
5
20
$$\text{mC}.{\text{m}}^{-2}$$
mC.m-2
whereas
$${C}_{0}=10
10
decreases
65%
same
This
study
provides
valuable
insights
into
their
potential
applications
nanoelectronic
devices.
Physics of Fluids,
Год журнала:
2024,
Номер
36(11)
Опубликована: Ноя. 1, 2024
Soft
bipolar
nanochannels
provide
distinct
and
valuable
understanding
of
the
intricate
relationship
among
shape,
charge
distribution,
concentration,
flow
dynamics.
This
study
investigates
intriguing
realm
nanoscale
structures,
where
two
configurations
soft
layers
with
varying
charges
an
but
appealing
setting
for
movement
management
ions,
as
well
regulation
control
ionic
species
in
five
various
geometries.
It
generates
cylindrical,
trumpet,
dumbbell,
hourglass,
conical
forms.
The
are
coated
a
diffuse
polyelectrolyte
layer,
density
distribution
layer
is
described
using
step
function.
To
enhance
accuracy,
impact
partitioning
taken
into
account.
investigate
effect
polarity,
types
were
considered:
Type
I
II.
In
I,
negative
pole
at
start,
while
II,
positive
start.
Thus,
features
arrangement
negative–positive
(NP),
whereas
II
has
positive–negative
(PN)
configuration.
research
was
conducted
under
stationary
conditions
finite
element
method,
Poisson–Nernst–Planck,
Navier–Stokes
equations.
By
manipulating
variables
such
order,
bulk
numerical
analysis
performed
to
these
on
current–voltage
parameters.
results
demonstrate
serves
more
effective
receiver
generating
greater
rectification.
For
instance,
dumbbell-shaped
nanochannel
exhibits
rectification
2046
concentration
1
mM
lowest
layer.
From
alternative
perspective,
conductivity
significantly
influenced
by
concentration.
study's
findings
fundamental
principles
have
profound
implications
diverse
applications
nanochannels.
capacity
regulate
manipulate
ion
transport
through
can
result
enhanced
efficiency,
selectivity,
performance
processes.
