Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Shape and surface anisotropy effects on the hysteresis of ferrimagnetic
  nanoparticles
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
6
The categories of this paper are: astro-ph
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
7
The categories of this paper are: hep-th
18
The categories of this paper are: econ