Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A singular perturbation approach to the steady-state 1D
  Poisson-Nernst-Planck modeling   The reduced 1D Poisson-Nernst-Planck (PNP) model of artificial nanopores in
the presence of a permanent charge on the channel wall is studied. More
specifically, we consider the limit where the channel length exceed much the
Debye screening length and channel's charge is sufficiently small. Ion
transport is described by the nonequillibrium steady-state solution of the PNP
system within a singular perturbation treatment. The quantities, 1/lambda --
the ratio of the Debye length to a characteristic length scale and epsilon --
the scaled intrinsic charge density, serve as the singular and the regular
perturbation parameters, respectively. The role of the boundary conditions is
discussed. A comparison between numerics and the analytical results of the
singular perturbation theory is presented.

33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom
14
The categories of this paper are: math-ph
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn