http://nopr.niscpr.res.in/handle/123456789/57789 2026-10-10T20:35:14Z 2026-10-10T20:35:14Z Priya, P Jayaseelan, P Vedanayaki, S http://nopr.niscpr.res.in/handle/123456789/57796 2021-08-10T05:48:12Z 2021-07-01T00:00:00Z

Title: Synthesis, spectral characterisation and pharmacological studies on Co(II), Ni(II), Cu(II) and Zn(II) bis-Schiff base complexes derived from 4-hydroxybenzohydrazide Authors: Priya, P; Jayaseelan, P; Vedanayaki, S Abstract: The transition metal(II) chelates have been prepared by the reactions of bis-Schiff base ligands derived from 4-hydroxy benzohydrazide and isophthalaldehyde/ o-phthaldehyde in 1:1 metal to ligand ratio. The formed ligands and their metal complexes have been investigated by elemental analysis, different spectroscopic and thermal analyses techniques. The low molar conductance values give the non-electrolytic nature of the metal(II) chelates. From the spectroscopic observations of complexes, the molecular formula is found to be [M(Ln)2Cl2] (where M= Co(II), Ni(II), Cu(II) and Zn(II), n=1 and 2) and the tetradentate N2O2 donor sites of ligands is attached to the metal centre. The docking results predicts that the protein with ligands have good interaction energy. All formed complexes have efficient antibacterial activity than ligand for tested pathogens. The mode of binding interaction of ct-DNA and Cu(II) complexes gives the intercalative binding with hypochromism shifts using electronic titrations method. In electrophoresis, cleavages of PUC18DNA to cleave effectively with Cu(II) complexes in the presence of hydroxyl radicals. The antioxidant assay of DPPH radical scavenging activity of tested compounds shows good results, when compared to ascorbic acid as standard. The anticancer MTT assay of Cu(II) complexes tested against MCF-7 cancerous cells gives the promising therapeutic activity. Page(s): 915-926

2021-07-01T00:00:00Z Gain, Sekhar http://nopr.niscpr.res.in/handle/123456789/57795 2021-07-30T05:07:44Z 2021-07-01T00:00:00Z

Title: Kinetics and mechanistic studies for oxidation of N-benzylhydroxylamine by a CoIII-bound bridging superoxo complex in perchloric acid medium Authors: Gain, Sekhar Abstract: In aqueous perchloric acid medium (pH = 0.522 – 1.3), N–benzylhydroxylamine (two electron reductant) reduces the one electron oxidant, superoxo ligand in [(dien)(en)CoIII(O2)CoIII(en)(dien)](ClO4)5 (1) to the corresponding hydroperoxo complex,[(en)(dien)CoIII(HO2)CoIII(en)(dien)]5+ (2) and itself gets oxidised to PhCH2NO following both proton coupled electron transferpath and an electron transfer reaction. The kinetics, stoichiometry and reaction mechanism clearly indicate that oxidation of PhCH2NHOH occurs through the formation of an intermediate, benzyl derivative of aminoxyl radical (PhCH2NHO•). In thepresence of excess PhCH2NHOH over 1, the reaction obeys first-order kinetics and rate of the reaction increases with [PhCH2NHOH]. The reaction rate, however, decreases with increase in [H+] and the plot of 1/ko with [H+] is linear with a smallbut noteworthy intercept. It is also remarked that the reaction rate remarkably decreases with increasing proportion of D2O replacing H2O in the solvent. Therefore, an H-atom transfer from PhCH2NHOH to the bridging superoxide in 1 seems reasonable at the rate determining step Page(s): 927-931

2021-07-01T00:00:00Z Chu, Yuanyuan Deng, Bohan Wang, Kuixiao Xue, Yu Tan, Xiaoyao http://nopr.niscpr.res.in/handle/123456789/57794 2021-07-30T05:05:41Z 2021-07-01T00:00:00Z

Title: Highly dispersed and ultrafine Co3O4@N-doped carbon catalyst derived from metal-organic framework for efficient oxygen reduction reaction Authors: Chu, Yuanyuan; Deng, Bohan; Wang, Kuixiao; Xue, Yu; Tan, Xiaoyao Abstract: Electrocatalysts are composed of transition metal/metal oxide and N-doped carbon can overcome the sluggish kinetics of oxygen reduction reactio. Herein, the Co3O4/ketjen black (KB)@MOF-derived with uniformly dispersed and ultrafine Co3O4 nanoparticles (1-5 nm) are synthesized by a facile in-situ method and subsequent mild pyrolysis process. It exhibits enhanced activity with onset potential of 0.96 V (vs. RHE) and a half-wave potential of 0.86 V (vs. RHE) in 0.1 M KOH solution, the excellent durability with E1/2 a small negative shift of 10 mV after 5000 continuous cycles and good methanol-tolerance property. The ultrahigh catalytic performance of Co3O4/KB@MOF-derived can be ascribed to the small particle size range of 1-5 nm of Co3O4, as well as the strong interaction between the in-situ formed N-Co3O4 active sites and substrate under the mild calcination temperature. Above all, these indicate that the as-prepared Co3O4/KB@MOF-derived may be a good alternative to commercial Pt-based catalysts. Page(s): 932-937

2021-07-01T00:00:00Z Ozturk, Esra Karacaoglu, Erkul http://nopr.niscpr.res.in/handle/123456789/57793 2021-07-30T05:02:59Z 2021-07-01T00:00:00Z

Title: Synthesis and photoluminescence analysis of Y1.50Sc0.50O3:Sm3+ andY1.50Sc0.50O3:Dy3+ phosphors Authors: Ozturk, Esra; Karacaoglu, Erkul Abstract: In this study, Y1.50Sc0.50O3:Sm3+ and Y1.50Sc0.50O3:Dy3+ have been synthesized by a solid state reaction method and theirphotoluminescence (PL) properties have been investigated. Single-phase and well-crystallized cubic Y1.50Sc0.50O3:Sm3+ andY1.50Sc0.50O3:Dy3+ phosphors are obtained after calcinations at 800 ºC and 900 ºC for 6 h. X-ray diffraction patterns confirm that both phosphors have a cubic phase without secondary phase. According to scanning electron microscope results, the particle size of both phosphors exhibit relatively irregular and their particle size are determinated to be between 0.27 μm–0.70 μm and 0.25 μm–2.04 μm for Y1.50Sc0.50O3:Sm3+ and Y1.50Sc0.50O3:Dy3+, respectively. The PL excitation and emissionspectra are recorded for both types of the phosphors. Emission spectra of Y1.50Sc0.50O3:Sm3+ and Y1.50Sc0.50O3:Dy3+ arefound to be typical for Sm3+and Dy3+. Page(s): 938-942

2021-07-01T00:00:00Z