LiNi 0.8 Co 0.2 O 2 cathode powders for lithiumion batteries were prepared by a modified sol-gel method with citric acid as chelating agent and a small amount of hydroxypropyl cellulose as dispersant agent. The structure and morphology of LiNi 0.8 Co 0.2 O 2 powders calcined at various temperatures for 4 h in air were characterized by means of powder X-ray diffraction analyzer, scanning electron microscope, thermogravimetric analyzer and differential thermal analyzer, and Brunauer-Emmett-Teller specific surface area analyzer. The results show that LiNi 0.8 Co 0.2 O 2 powders calcined at 800°C exhibit the best layered structure ordering and appear to have monodispersed particulates surface. In addition, the electrochemical properties of LiNi 0.8 Co 0.2 O 2 powders as cathode material were investigated by the charge-discharge and cyclic voltammetry studies in a three-electrode test cell. The initial charge-discharge studies indicate that LiNi 0.8 Co 0.2 O 2 cathode material obtained from the powders calcined at 800°C shows the largest charge capacity of 231 mAh g -1 and the largest discharge capacity of 191 mAh g -1 . And, the cyclic voltammetry studies indicate that Li ? insertion and extraction in LiNi 0.8 Co 0.2 O 2 powders is reversible except for the first cycle.
The three-component reaction of isoquinoline, dialkyl but-2ynedioate and 4-arylidene-5-methyl-2-phenylpyrazol-3-ones in acetonitrile at room temperature gave functionalized spiro [pyrazole-4,1'-pyrido[2,1-a]isoquinolines] in satisfactory yields with cis/cis-diastereoisomer as major product. On the other hand, the similar three-component reaction with quinoline afforded both cis/cis-and cis/trans-isomeric spiro[pyrazole-4,4'pyrido[1,2-a]quinolines] in nearly comparable yields. The reaction was finished with in situ generation of Huisgen' 1,4-dipole, sequential Michael addition and annulation reaction process.
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