Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Combinatorial Search for Optimal Hydrogen-Storage Nanomaterials Based on
  Polymers
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
22
The categories of this paper are: chao-dyn
9
The categories of this paper are: nlin
24
The categories of this paper are: dg-ga
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
27
The categories of this paper are: comp-gas
1
The categories of this paper are: cs
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc