http://nopr.niscair.res.in/handle/123456789/518 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/2236 Title: Effect of organic fuels on catalytic properties of La₀․₈Sr₀․₂CoO₃ with large surface area <br/> <br/>Authors: Liu, Wei; Laitao; Wu, Yuehui <br/> <br/>Abstract: Perovskite-type La₀․₈Sr₀․₂CoO₃ oxides have been prepared by solution combustion synthesis and their catalytic performance for CH₄ combustion reaction has been studied. The prepared samples have been characterized by XRD, IR. BET and TPR. The effect of organic fuels on the struclllre and the catalytic activities of La₀․₈Sr₀․₂CoO₃ catalysts have been investigated. Results indicate that all the La₀․₈Sr₀․₂CoO₃ catalysts prepared by solution combustion synthesis have large specific surface area, and the structure and catalytic activities of the catalysts are related to the organic fuels. The best catalytic activity is shown by the La₀․₈Sr₀․₂CoO₃ catalyst prepared with DL-alanine. The activity of the catalyst can be explained in terms of smaller crystallite size, larger specific surface area, lower activation energy and more mobility of chemisorbed oxygen on the surface and in the vacancies. <br/> <br/>Page(s): 194-198 http://nopr.niscair.res.in/handle/123456789/604 Title: Calix[6]arene derivative as chromogenic sensor for anti-hypertensive drugs <br/> <br/>Authors: Menon, S K; Jose, P; Harikrishnan, U; Pal, U <br/> <br/>Abstract: A simple, rapid, and sensitive spectrophotometric method has been developed for the determination of atenolol, propranolol hydrochloride and metaprolol tartarate. The method is based on the reaction of these drugs as n-electron donors with acceptor groups on macrocyclic ring of calixarene. Due to the rapid development of color at ambient temperatures, the chromogenic calix[6]arene derivative can be used for the determination of these -adrenergic blocking drugs. The association constants (KcAD) and free energies for the complexes have been determined. The proposed method can be used to determine the drugs in pharmaceutical tablets and urine. <br/> <br/>Page(s): 246-250 http://nopr.niscair.res.in/handle/123456789/602 Title: Determination of pKa of ammonium and phenolic groups: Evidence of intramolecular hydrogen bonding in aqueous solution <br/> <br/>Authors: Sim, Yoke-Leng; Ahmad, Wan Hamdah Wan; Ariffin, Azhar; Khan, M Niyaz <br/> <br/>Abstract: The ionization constants of 2-hydroxyanilinium, 2-methoxyanilinium, 4-nitroanilinium ions, N-(2′-hydroxyphenyl)-phthalamic acid and N-(2′-methoxyphenyl) phthalamic acid, determined spectrophotometrically, have been rationalized in terms of internal hydrogen bonding and steric hindrance between o–substituent and reaction site. <br/> <br/>Page(s): 240-245 http://nopr.niscair.res.in/handle/123456789/600 Title: Computational studies and reactivity of nucleophiles in benzylation reactions <br/> <br/>Authors: Reddy, S Ranga; Kalyani, P; Rao, B Rajeswara; Manikyamba, P <br/> <br/>Abstract: The nucleophilic substitution reactions of benzyl bromide using 2-mercapto benzimidazole, 2-mercaptobenzoxazole and 2-mercaptobenzothiazole as nucleophiles have been studied in methanol and acetone media. The higher reactivity of 2-mercaptobenzimidazole is attributed to the presence of two nitrogen atoms holding a pair of electrons on either side of the >C=S group. The heat of formation, Δ Hf, computed from AM1 studies indicates that the reactivity of the nucleophiles is related to Δ Hf, and HOMO-LUMO gap of the nucleophile. <br/> <br/>Page(s): 236-239