Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The vacuum thermal treatment effect on the optical absorption spectra of
  the TiO2 coated by Ni-B nano-clasters photocatalyst powders   The thermal vacuum treatment effect on the optical absorption spectra of the
TiO2 nanopowders, both pure and coated by the Ni-B clasters with the original
electroless method was investigated. It was observed that the thermal treatment
of pure TiO2 nanopowders does not change their optical absorption spectrum
while after the coating of these powder particles by the Ni-B clasters the
thermal treatment results in the increase of the optical light absorption in
the visual region of spectrum. This points to the possibility of the
significant improvement of the photocatalist efficiency of TiO2 nanopowders
coated by the Ni-B clasters using the thermal treatment.

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The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
21
The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
27
The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th
26
The categories of this paper are: bayes-an
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg