EFFECT OF THE NITRATE FERTILIZER UREA ON THE ULTRASTRUCTURAL CHANGES IN THE GILL OF FRESHWATER FISH CATLA

Ultrastructural study of the gill of Catla catla on exposure to 10% LC 50 sublethal concentration of nitrate fertilizer urea was carried out. Hypertrophy and hyperplasia of the lamellar cells in combination with epithelial lifting and edema were noticed. Necrosis of pillar system with lamella resulted in blood congestion and even an aneurism. Hyper secretion of mucous on the epithelium is to protect against environmental alteration was also determined. Infiltrated macrophages and leucocytes in the lamellar tissue were observed which was a compensatory repair response to tissue damages. Apoptotic condition of the cell is evident by clumping of chromatin, swelling of nucleus and mitochondria

Li3MxV22x(PO4)3/C (M=Fe, Co) composite cathodes with extended solubility limit and improved electrochemical behavior

A first attempt has been made to prepare Li3MxV22x(PO4)3/C (M=Fe, Co) composite solutions by adopting a novel oxalic dihyrazide assisted combustion (ODHAC) method. The pillaring effect of Fe in Li3FexV22x(PO4)3/C and the possible electrochemical activity of the Co3+/4+ redox couple of Li3CoxV22x(PO4)3/C at a 4.8 V limit increases the structural and cycling stability of the native Li3V2(PO4)3/C cathode respectively, thereby ultimately improving the electrochemical behaviour of Li3MxV22x(PO4)3/C solid solutions. An extended solubility limit of x = 0.10 for Fe dopant has been achieved for the first time through the present study against the reported value of x = 0.05 in Li3FexV22x(PO4)3/C compounds. The study demonstrates the suitability of the ODHAC synthesis approach in preparing a wide variety of phase pure Li3MxV22x(PO4)3/C cathodes. Further, the superiority of Li3Co0.10V1.90(PO4)3/C in exhibiting the highest capacity (178 mAh g21) and negligible fade (4%) and the demonstrated cyclability under the influence of 10 C rate has been understood as a function of the synergistic effect of the ODHAC synthesis method and the optimum concentration of Co dopant chosen for the stud

Combustion synthesized nanocrystalline Li3V2(PO4)3/C cathode for lithium-ion batteries

Nanocrystalline Li3V2(PO4)3/C composite synthesized using a novel corn assisted combustion method at 850 8C exhibits superior physical and electrochemical properties than the one synthesized at 800 8C. Despite the charge disproportionation of V4+ and a possible solid solution behavior of Li3V2(PO4)3 cathode upon insertion and extraction of Li+ ions, the structural stability of the same is appreciable, even with the extraction of third lithium at 4.6 V. An appreciable specific capacity of 174 mAh g�1 and better capacity retention upon high rate applications have been exhibited by Li3V2(PO4)3/C cathode, thus demonstrating the suitability of the same for lithium-ion battery application