Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Growth Process of Hexagonal Boron Nitride in the Diffusion and
  Precipitation Method Studied by X-ray Photoelectron Spectroscopy   Submonolayer h-BN was grown on Ni foil in ultra-high vacuum by the diffusion
and precipitation method and the growth process was studied by x-ray
photoelectron spectroscopy. Formation of h-BN started to be observed at 600 C.
All through the process, the surface was always slightly B-rich, which is
consistent with the fact that B which is soluble in Ni at a high temperature
can diffuse in Ni by the conventional bulk diffusion and insoluble N cannot.
Moreover, both formation and decomposition of h-BN were found to occur at
elevated temperatures possibly depending on provision of N atoms to the
surface. On the Ni surface, decomposition of h-BN was observed at a relatively
low temperature of 800 C.

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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: astro-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
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The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: physics
12
The categories of this paper are: nucl-th
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The categories of this paper are: eess
0
The categories of this paper are: hep-ph