Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Comparative study of microwave absorption in Ni/SiO2 and SiO2/Ni
  core-shell structures   Ni coated SiO2 and SiO2 coated Ni composite particles with core-shell
structures were designed, prepared and their microwave absorption properties
were characterized. The comparison study of the shell effect on the effective
electromagnetic parameters reveals that the effective permittivity/permeability
was crucially determined by the percent and the intrinsic electromagnetic
parameters of the component materials regardless of various core/shell
structures. Both of the composite core-shell structures could have good
microwave absorption properties. Investigation of the input impedance indicates
that, good microwave absorption performances are a consequence of proper
electromagnetic impedance matches when the effective electromagnetic parameters
were modulated.

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The categories of this paper are: astro-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: q-bio
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The categories of this paper are: acc-phys
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The categories of this paper are: hep-ph
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: solv-int
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The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: q-alg
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The categories of this paper are: adap-org