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101.
Synthesis,structural characterisation and electrochemical and antibacterial studies of Schiff base copper complexes 总被引:1,自引:0,他引:1
Raman Natarajan Kulandaisamy Antonysamy Thangaraja Chinnathangavel Manisankar Paramasivan Viswanathan Subramanian Vedhi Chinnapayan 《Transition Metal Chemistry》2004,29(2):129-135
Neutral complexes of CuII have been synthesised from the Schiff bases derived from salicylidene-4-aminoantipyrine and PhNH2/substituted anilines. The structural features have been determined from their microanalytical, i.r., u.v.–vis., 1H-, 13C-n.m.r., mass and e.s.r. spectral data. All the complexes exhibit square-planar geometry. Their magnetic susceptibility measurements and low conductance data provide evidence for the monomeric and non-electrolytic natures of the complexes respectively. The electrochemical behaviour of the complexes in MeCN at 298 K was studied. The kinetic parameters were determined and are discussed. The X-band e.s.r. spectra of the complexes in DMSO at 300 and 77 K were recorded and their salient features are reported. The powder XRD diffraction patterns for all the complexes are found to be similar. The antimicrobial activity of the ligands and their copper complexes against the bacteria Staphylococcus aureus, Klebsiella pneumoniae, Salmonella typhi, Pseudomonas aerugenosa and Bacillus subtilis are also reported. The complexes have higher activities than those of the free Schiff bases. Moreover, they have higher activity than the control (ampicillin) except for Klebsiella pneumoniae and Pseudomonas aerugenosa. 相似文献
102.
The results of a comparative study of nickel oxide-alumina and nickel oxide-silica alumina catalysts in the light of the characteristics of the support systems alumina and silica-alumina are presented. The impregnation of NiO does not produce any significant change in the textural characteristics like surface area and pore volume of the support oxides. However the deposited nickel oxide leads to the modification of the surface acidity determined by Hammett indicators. In the case of parent oxides the ammonia adsorption is strong (from heat of adsorption measurement) for alumina and silica-alumina, though for the former it is slightly stronger at comparable surface coverages. But the adsorption of ammonia on NiO? Al2O3 is weak while it is strong on NiO/SiO2? Al2O3 at the same comparable surface coverages. The reduction in acidity is reflected in the poor dehydration and absence of skeletal isomerisation on NiO impregnated catalysts. 相似文献
103.
S. Chitra S. Viswanathan S. V. S. Rao P. K. Sinha 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(3):955-960
Crystalline silicotitanate inorganic ion exchanger, with a sitinakite structure is candidate material for remediation of aqueous
nuclear waste streams. The syntheses of crystalline silicotitanate (CST) and Nb-substituted crystalline silcotitanate (Nb-CST)
were carried out under hydrothermal conditions and the products were characterized using techniques viz., XRD, SEM/EDS, DTA/TGA,
surface area respectively. Batch experiments were carried out to study the kinetics of uptake of 137Cs and 90Sr, to estimate the decontamination factor (DF) values and distribution coefficients (K
d) for the above synthesized CST and Nb-CST samples from actual radioactive waste solutions. The DF values for uptake of Cs
and Sr by Nb-CST after 24 h of equilibration was 355 and 136 whereas for CST it was found to be 40 and 176 respectively. The
K
d values for uptake of Cs and Sr for Nb-CST after 24 h of equilibration was found to be 35,490 and 13,500 mL/g respectively
whereas the K
d values for uptake of Cs and Sr for CST was found to be 4,025 and 17,525 mL/g respectively. The ion exchange capacity of Nb-CST
towards 90Sr and 137Cs was estimated to be 11.8 and 3.2 meq/g respectively whereas the ion exchange capacity of CST towards 90Sr and 137Cs was estimated to be 14.6 and 4.4 meq/g respectively. 相似文献
104.
Rathnasamy Rajeswari Thangasamy Pitchai Aravindhan Vanangamudi Sathyanarayanan Punniyakoti Alagan Viswanathan 《Research on Chemical Intermediates》2019,45(6):3571-3584
Research on Chemical Intermediates - Preparation of semiconductor nanomaterials with controlled morphology and uniform porous surface is of great interest for enhanced photocatalytic applications.... 相似文献
105.
Tina Kapur Jan Egger Antonio Damato Ehud J. Schmidt Akila N. Viswanathan 《Magnetic resonance imaging》2012
Gynecologic malignancies are a leading cause of death in women worldwide. Standard treatment for many primary and recurrent gynecologic cancer cases includes external-beam radiation followed by brachytherapy. Magnetic resonance (MR) imaging is beneficial in diagnostic evaluation, in mapping the tumor location to tailor radiation dose and in monitoring the tumor response to treatment. Initial studies of MR guidance in gynecologic brachytherapy demonstrate the ability to optimize tumor coverage and reduce radiation dose to normal tissues, resulting in improved outcomes for patients. 相似文献
106.
107.
Dr. Shannon J. Lee Gayatri Viswanathan Dr. Scott L. Carnahan Dr. Colin P. Harmer Dr. Georgiy Akopov Prof. Dr. Aaron J. Rossini Prof. Dr. Gordon J. Miller Prof. Dr. Kirill Kovnir 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(9):e202104319
Centrosymmetric skutterudite RhP3 was converted to a nonsymmorphic and chiral compound RhSi0.3P2.7 (space group P212121) by means of partial replacement of Si for P. The structure, determined by a combination of X-ray crystallography and solid state 31P NMR, exhibits branched polyanionic P/Si chains that are unique among metal phosphides. A driving force to stabilize the locally noncentrosymmetric cis-RhSi2P4 and fac-RhSi3P3 fragments is π-electron back-donation between the Rh t2g-type orbitals and the unoccupied antibonding Si/P orbitals, which is more effective for Si than for P. In situ studies and total energy calculations revealed the metastable nature of RhSi0.3P2.7. Electronic structure calculations predicted centrosymmetric cubic RhP3 to be metallic which was confirmed by transport properties measurements. In contrast, the electronic structure for chiral orthorhombic RhSi0.3P2.7 contained a bandgap, and this compound was shown to be a narrow gap semiconductor. 相似文献
108.
109.
J. Tiley K. Shiveley G.B. Viswanathan C.A. Crouse A. Shiveley 《Micron (Oxford, England : 1993)》2010,41(6):615-621
A low-stress automated polishing device was developed for preparing titanium and nickel alloys for scanning electron microscopy imaging. The system used pulsed electrochemical reactions within an alkaline electrolyte to generate a thin passivation layer on the surface of the sample, which was removed by the mechanical vibration of the system. The passivation layer development and removal were documented for Ti–6Al–4V and IN718 samples subjected to varying electrical potential cycles and polishing times. Results indicated that the applied cyclic potentials removed material faster than typical removal techniques. In addition, electron back scatter diffraction data showed a decrease in subsurface damage using the developed electrochemical–mechanical process compared to standard mechanical polishing techniques. 相似文献
110.
Rong Kou Yuyan Shao Donghai Wang Mark H. Engelhard Ja Hun Kwak Jun Wang Vilayanur V. Viswanathan Chongmin Wang Yuehe Lin Yong Wang Ilhan A. Aksay Jun Liu 《Electrochemistry communications》2009,11(5):954-957
Electrocatalysis of oxygen reduction using Pt nanoparticles supported on functionalized graphene sheets (FGSs) was studied. FGSs were prepared by thermal expansion of graphite oxide. Pt nanoparticles with average diameter of 2 nm were uniformly loaded on FGSs by impregnation methods. Pt-FGS showed a higher electrochemical surface area and oxygen reduction activity with improved stability as compared with the commercial catalyst. Transmission electron microscopy, X-ray photoelectron spectroscopy, and electrochemical characterization suggest that the improved performance of Pt-FGS can be attributed to smaller particle size and less aggregation of Pt nanoparticles on the functionalized graphene sheets. 相似文献