Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Super-Diffusive Gas Recovery from Nanopores   Understanding the recovery of gas from reservoirs featuring pervasive
nanopores is essential for effective shale gas extraction. Classical theories
cannot accurately predict such gas recovery and many experimental observations
are not well understood. Here we report molecular simulations of the recovery
of gas from single nanopores, explicitly taking into account molecular gas-wall
interactions. We show that, in very narrow pores, the strong gas-wall
interactions are essential in determining the gas recovery behavior both
quantitatively and qualitatively. These interactions cause the total diffusion
coefficients of the gas molecules in nanopores to be smaller than those
predicted by kinetic theories, hence slowing down the rate of gas recovery.
These interactions also lead to significant adsorption of gas molecules on the
pore walls. Because of the desorption of these gas molecules during gas
recovery, the gas recovery from the nanopore does not exhibit the usual
diffusive scaling law (i.e., the accumulative recovery scales as $R \sim
t^{1/2}$ but follows a super-diffusive scaling law $R \sim t^n$ ($n>0.5$),
which is similar to that observed in some field experiments. For the system
studied here, the super-diffusive gas recovery scaling law can be captured well
by continuum models in which the gas adsorption and desorption from pore walls
are taken into account using the Langmuir model.

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The categories of this paper are: quant-ph
1
The categories of this paper are: cs
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The categories of this paper are: hep-lat
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The categories of this paper are: math-ph
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
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The categories of this paper are: stat
18
The categories of this paper are: econ
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The categories of this paper are: nucl-th
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The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat