Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Role of precursor composition in the polymorph transformations,
  morphology control and ferromagnetic properties of nanosized TiO$_2$   Pure phase and mixed phase TiO$_2$ nanoparticles have been produced using a
pyrolytic method from a non-aqueous carboxylate precursor. The precursor was
prepared by a multiphase cation exchange using pentanoic acid (C$_4$H$_9$COOH).
The thermal stability, polymorph content, morphology, size distribution and
surface region of the produced nanoparticles were studied by TGA/DSC, XRD, FTIR
and TEM. High quality monodisperse nanoparticles have been produced in the size
range from 7 to 27 nm. The nanoparticles showed room temperature ferromagnetism
revealed by VSM within bound polaron model. The carboxylate precursor is a good
alternative to standard sol-gel to produce nanoparticles free from impurities.

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The categories of this paper are: chem-ph
8
The categories of this paper are: hep-ex
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
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The categories of this paper are: plasm-ph
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci