Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Adhesion and size dependent friction anisotropy in boron nitride
  nanotubes   The frictional properties of individual multiwalled boron nitride nanotubes
(BN-NTs) synthesized by chemical vapor deposition (CVD) and deposited on a
silicon substrate are investigated using an atomic force microscope tip sliding
along (longitudinal sliding) and across (transverse sliding) the tube's
principal axis. Because of the tube transverse deformations during the tip
sliding, a larger friction coefficient is found for the transverse sliding as
compared to the longitudinal sliding. Here, we show that the friction
anisotropy in BN-NTs, defined as the ratio between transverse and longitudinal
friction forces per unit area, increases with the nanotube-substrate contact
area. Larger contact area denotes stronger surface adhesion, resulting in a
longitudinal friction coefficient closer to the value expected in absence of
transverse deformations. Compared to carbon nanotubes (C-NT), BN-NTs display a
friction coefficient in each sliding direction with intermediate values between
CVD and arc discharge C-NTs. CVD BN-NTs with improved tribological properties
and higher oxidation temperature might be a better candidate than CVD C-NTs for
applications in extreme environments.

15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
27
The categories of this paper are: comp-gas