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Coprecipitation combined with high temperature melting,a brand
new powder preparation technique derived from the conventional
chemical coprecipitation,was applied to the synthesis of
lanthanum copper oxides.Processes were perfomed with the
corresponding metal chloride and sodium hydroxide in the
ethanol solution.In the study,we investigated the role of NaCl
as well as the influence of copper-substituted and lanthanum-
substituted on electric and magnetic properties of La2CuO4
specimens. It was found in this exploration that owing to fused
salts the temperature of the formation of lanthanum copper
oxides was decreased to 600oC upon calcining and the other
effects on the morphology and crystalline structural phases of
La2CuO4 powders were proved.The content of NaCl could be
controlle by the ratio [OH-]/[Mn+] in this system.While the
above value was greater than 3.33,discrete plate-like particles
with the K2NiF4 structure of tetragonal phase were obtained.
Howere the above value was smaller than 2.00,uniform sphereical
ones with orthorhombic distortion phase could be prepared.
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