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LiCr 0.2 Ni 0.4 Mn 1.4 O 4 was synthesized by a sol-gel technique in which tartaric acid was used as oxide precursor. The synthesized powder was annealed at five different temperatures from 600 to 1,000°C and tested as a 5-V cathode material in Li-ion batteries. The study shows that annealing at higher temperatures resulted in improved electrochemical performance, increased particle size, and a differentiated surface composition. Spinel powders synthesized at 900°C had initial discharge capacities close to 130 mAh g −1 at C and C/2 discharge rates. Powders synthesized at 1,000°C showed capacity retention values higher than 85 % at C/2, C, and 2C rates at 25°C after 50 cycles. Annealing at 600-800°C resulted in formation of spinel particles smaller than 200 nm, while almost micron-sized particles were obtained at 900-1,000°C. Chromium deficiency was detected at the surface of the active materials annealed at low temperatures. The XPS results indicate presence of Cr 6+ impurity when the annealing temperature was not high enough. The study revealed that increased annealing temperature is beneficial for both improved electrochemical performance of LiCr 0.2 Ni 0.4 Mn 1.4 O 4 and for avoiding formation of Cr 6+ impurity on its surface.

Malignant melanoma with its varied clinical presentations and histomorphological patterns is a perplexing problem both for the diagnosticians and clinicians. a small proportion of melanomas present with metastatic tumors with unknown primary sites and at these sites they mimic the more common primary neoplasms. We hereby report a case of malignant melanoma presenting as a submandibular lump in a 40 year old female. This lump was present for six months and was rapidly increasing in size. on cytology it was diagnosed as salivary gland neoplasm.