Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electronic Transport through YBCO Grain Boundary Interfaces between 4.2
  K and 300 K   The current-induced dissipation in YBCO grain boundary tunnel junctions has
been measured between 4.2 K and 300 K. It is found that the resistance of 45
degree (100)/(110) junctions decreases linearly by a factor of four when their
temperature is increased from 100 K to 300 K. At the superconducting transition
temperature Tc the grain boundary resistance of the normal state and of the
superconducting state extrapolate to the same value.

16
The categories of this paper are: stat
32
The categories of this paper are: atom-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
13
The categories of this paper are: quant-ph
11
The categories of this paper are: hep-lat
18
The categories of this paper are: econ
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
2
The categories of this paper are: math