Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhancement of Tc by Sr substitution for Ba in Hg-2212 superconductor   The Ba substitution by Sr has been studied in two Hg-2212 series:
Hg2(Ba(1-y)Sr(y))2YCu2O8-d and Hg2(Ba(1-y)Sr(y))2(Y0.80Ca0.20)Cu2O8-d. In both
series a Tc enhancement of about 40 K is observed when Sr substitutes Ba from y
= 0 to y = 1.0.
  The y = 0 compound of the first series is the non superconducting
Hg2Ba2YCu2O8-d prototype. In the second series, this y = 0 compound is already
superconducting at 21 K. Indeed the members of this series present a higher
charge carrier density in their CuO2 superconducting planes than their
homologues of the first series due to the doping introduced by the substitution
of 20% of Y by Ca. The compounds of both series were synthesized in high
pressure (3.5 GPa) - high temperature (950 - 1050C) conditions. In both cases
Sr substitution was successful up to the full replacement of Ba (y = 1.0). The
Hg-2212 phases were characterized by XRD, SEM, EDX and a.c. susceptibility.

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The categories of this paper are: acc-phys
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
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The categories of this paper are: comp-gas
12
The categories of this paper are: nucl-th