Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structural, Microchemistry, and Hydrogenation Properties of
  TiMn0.4Fe0.2V0.4,TiMn0.1Fe0.2V0.7 and Ti0.4Zr0.6Mn0.4Fe0.2V0.4 Metal Hydrides   In this work, TiFe-based alloys have been developed according to the
stoichiometry Ti1-xAxFe1-yBy (A \equiv Zr; B \equiv Mn, V). The hydrogen
solubility properties have been investigated to develop dynamic hydrides of
Ti-based alloys for hydrogen storage applications. The hydrogenation behavior
of these alloys has been studied, and their hydrogen storage capacities and
kinetics have been evaluated. Several activation modes, including activation at
high temperatures under hydrogen pressure, have been attempted for the
as-milled powders. In order to clarify the structural / microstructural
characteristics, and chemical composition before and after hydrogenation, X-Ray
Diffraction (XRD), EDAX - Mapping Analysis and Scanning Electron Microscopy
(SEM), have been carried out for the samples. Modeling of the isotherms has
been performed by using MATLAB programming. The maximum gravimetric density of
4.3 wt%, has been obtained on the sample with the BCC main phase. The
calculated enthalpy of reaction ({\Delta}H) is found to be about 4 kJ/mol.

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The categories of this paper are: cmp-lg
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The categories of this paper are: astro-ph
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The categories of this paper are: quant-ph
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The categories of this paper are: adap-org
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The categories of this paper are: hep-lat
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The categories of this paper are: patt-sol
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The categories of this paper are: alg-geom
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: acc-phys
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The categories of this paper are: chem-ph
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The categories of this paper are: plasm-ph
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The categories of this paper are: math-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: q-fin