Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Synthesis and structural characterization of uranium-doped Ca2CuO3, a 1D
  quantum antiferromagnet   The technological settings of a modified sol-gel method for preparation of
highly fine homogeneous powder Ca2CuO3 doped with uranium 238 (x=0-0.05) is
presented. The analysis of structure, purity of phases and the justification
for the role of uranium in the given compounds are provided together with
almost complete classification of observed optical phonons by means of the
Raman, IR measurements and ab initio calculation. The significant reduction in
particle size was achieved by doping and the strong correlation between
resistivity and doping concentration was observed and explained using the
phonon-assisted electron hopping conduction model. The persistence of covalent
insulation state in all compounds is a key feature of this class of compounds.

14
The categories of this paper are: math-ph
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
7
The categories of this paper are: hep-th