Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Brownmillerite Ca2Co2O5: Synthesis, Stability, and Re-entrant
  Single-Crystal-to-Single-Crystal Structural Transitions
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
2
The categories of this paper are: math