Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Measuring magnetic moments of polydisperse ferrofluids utilizing the
  inverse Langevin function   The dipole strength of magnetic particles in a suspension is obtained by a
graphical rectification of the magnetization curves based on the inverse
Langevin function. The method yields the arithmetic and the harmonic mean of
the particle distribution. It has an advantage compared to the fitting of
magnetization curves to some appropriate mathematical model: It does not rely
on assuming a particular distribution function of the particles.

8
The categories of this paper are: hep-ex
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The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
29
The categories of this paper are: funct-an
5
The categories of this paper are: gr-qc
16
The categories of this paper are: stat
11
The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
14
The categories of this paper are: math-ph
17
The categories of this paper are: q-fin
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The categories of this paper are: eess