Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effects of the Position Reversal of Friction Pairs on the Strength of
  Tribocharging and Tribodischarging   The friction-induced charging (i.e., tribocharging) and the following
discharging (referred here as tribodischarging) are always believed to have
negative effects on the daily life and on the industrial production. Thus, how
to inhibit the tribocharging and the tribodischarging has caused wide public
concern. Because the discharge caused by the electrical breakdown of the
ambient gas is generally accompanied with the generation of light, we
investigated here the tribocharging and the tribodischarging by observing the
light emitted during friction. We found that the position reversal of the
friction pair has a dramatic impact on the intensity of the tribo-induced
light. Experimental results show that an intense light is produced when a
stationary Al2O3 disk is sliding on a rotating SiO2 disk, but only a weak light
is observed for the case of a stationary SiO2 disk and a rotating Al2O3 disk.
This means that the process of the tribocharging and the tribodischarging can
be significantly influenced owing to the change in the relative position of the
friction couple. The experimentally measured polarities of the tribo-induced
charge on the friction surfaces further indicated that the strong discharging
occurs when the rotating surface is negatively charged. The reason for the
difference in the intensity of the tribocharging and tribodischarging can be
attributed to the combined effects of the contact potential difference and the
temperature gradient between the contacting surfaces on the charge transfer
when friction. Finally, a simple, low cost, yet effective approach, i.e., just
keep the friction partner whose surface is tribo-induced negatively charged as
the stationary one, can be utilized to suppress the intensity of the
tribocharging and the tribodischarging. This work may provide potential
applications in numerous areas of science and engineering and also in the
everyday life.

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The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
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The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
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The categories of this paper are: hep-th
9
The categories of this paper are: nlin
32
The categories of this paper are: atom-ph