Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Charge regulation and ionic screening of patchy surfaces   The properties of surfaces with charge-regulated patches are studied using
non-linear Poisson-Boltzmann theory. Using a mode expansion to solve the
non-linear problem efficiently, we reveal the charging behaviour of
Debye-length sized patches. We find that patches charge up to higher charge
densities if their size is relatively small and if the patches are well
separated. The numerical results are used to construct a basic analytical model
which predicts the average surface charge density on surfaces with patchy
chargeable groups.

13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
10
The categories of this paper are: q-bio
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
9
The categories of this paper are: nlin