Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effect of Chemical Structure on the Isobaric and Isochoric Fragility in
  Polychlorinated Biphenyls   Pressure-volume-temperature data, along with dielectric relaxation
measurements, are reported for a series of polychlorinated biphenyls (PCB),
differing in the number of chlorine atoms on their phenyl rings. Analysis of
the results reveals that with increasing chlorine content, the relaxation times
of the PCB become governed to a greater degree by density, rho, relative to the
effect of temperature, T. This result is consistent with the respective
magnitudes of the scaling exponent, gamma, yielding superpositioning of the
relaxation times measured at various temperatures and pressures, when plotted
versus rho^gamma/T. While at constant (atmospheric) pressure, fragilities for
the various PCB are equivalent, the fragility at constant volume varies
inversely with chlorine content. Evidently, the presence of bulkier chlorine
atoms on the phenyl rings magnifies the effect density has on the relaxation
dynamics.

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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
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The categories of this paper are: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: hep-ex
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The categories of this paper are: nlin
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The categories of this paper are: hep-th
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The categories of this paper are: comp-gas
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The categories of this paper are: econ
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The categories of this paper are: cmp-lg
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The categories of this paper are: hep-lat
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The categories of this paper are: physics
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The categories of this paper are: patt-sol