Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electrophoretic mobility without charge driven by spontaneous
  polarization of the nanoparticle/water interface   Polarization of the interface, spontaneously occurring when water is in
contact with hydrophobic solutes or air, couples with the uniform external
field to produce a non-zero force acting on a suspended particle. This force
exists even in the absence of a net particle charge, and its direction is
affected by the first-order, dipolar and the second-order, qudrupolar
orientational order parameters of the interfacial water. The quadrupolar
polarization gives rise to an effectively negative charge. The corresponding
surface charge density is inversely proportional to the area of the shear
surface. As a result, the overall contribution from the quadrupolar
polarization to the particle mobility becomes negligible compared to
experimentally reported values for particles exceeding a few nanometers in
size. The dipolar order of the interface dominates the zero-charge mobility of
sub-micron particles. The corresponding electrokinetic charge is determined by
the preferential orientation of interfacial dipoles relative to the surface
normal.

30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
14
The categories of this paper are: math-ph
26
The categories of this paper are: bayes-an
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
5
The categories of this paper are: gr-qc
35
The categories of this paper are: mtrl-th
23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess