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Item Complexes of 3-ethyl-4-benzylidene-5-mercapto-l,2,4-triazole with Cu(I), Ag(I), Tl(I), Zn(Il), Cd(II) and Pb(II) are prepared. Based on analytical data, spectral studies, magnetic measurement and oxidation state study, the probable structures have been proposed. Cu(I), Tl(I), Ag(I) complexes seem to be linear polymeric, while Zn(II), Cd(II) and Pb(II) complexes appear to be tetra-hedral chelates. © (1979), (Indian Academy of Sciences). All Rights Reserved.(Indian Academy of Sciences, PREPARATION AND CHARACTERISATION OF Cu(l), Ag(I), TI(I), Zn(II)f Cd(II) AND Pb(II) COMPLEXES WITH 3-ETHVL-4-BENZYLIDENE-5-MERCAPTO-l, 2, 4-TRIAZOLE) Gadag, R.V.; Gajendragad, M.R.1979Item BaCu(C2O4)2 · 6 H2O is triclinic, P1, with a = 6.5405(9), b = 9.202(3), c= 10.939(1) Å, ? = 8546(2), ? = 79.22(1), ? = 80.45(2), V = 636.99(1) Å3, Z=2, D0, = 2.14, Dc = 2.465 g · cm-3, R = 0.074. wR = 0.0746 for 2219 significant reflections |F0| = 6.0?F0. The barium has eleven coordinations and the coordination polyhedra is a capped antiprism. Six water oxygen atoms are coordinated whereas the other five are coming from the oxalate group. In the unit cell the molecules form a polymeric network. One lattice water molecule belongs to the coordinating water. The barium oxygen distances vary from 2.75 Å to 3.15 Å.(Wiley-VCH Verlag, The crystal structure of hydrated barium copper oxalate) Kasthuri, V.B.; Rao, P.M.; Nethaji, M.1996Item The ultrafast nonlinear optical response and multi-photon absorption of a new metal complex in the near-infrared spectral range(Institute of Physics Publishing, 2010) Kiran, A.J.; Lee, H.W.; Sampath Kumar, H.C.; Rudresha, B.J.; Badekai Ramachandra, B.; Yeom, D.-I.; Kim, K.; Rotermund, F.A new coordination compound, chloro(1,10-phenanthroline-N, N ?)(triphenylphosphine)copper(I) dichloromethane, incorporated in poly(methyl methacrylate) exhibits superior nonlinear optical properties in the near-infrared spectral region. Its nonlinear response time and third-order nonlinear optical susceptibility at 800nm are ? 90fs and 1.8 × 10 -10esu, respectively. Considerable nonlinear absorption is observed with this sample, near 800 and 1250nm. The contribution of the excited states to the total nonlinear absorption process is discussed. The results reveal the potential of this newly designed compound for multi-photon absorption-based photonic applications. © 2010 IOP Publishing Ltd.Item Synthesis, characterization and third-order nonlinear optical studies of copper complexes containing 1,10-phenanthroline-5,6-dione and triphenylphosphine ligands(2011) Rudresha, B.J.; Badekai Ramachandra, B.; Sampath Kumar, H.C.; Shivakumar, K.I.; Safakath, K.; Philip, R.This research article describes the synthesis, characterization and third-order nonlinear optical studies of copper(I) complexes [Cu(Br)(N,N?-C12H6N2O2) (PPh3)] and [Cu(I)(N,N?-C12H6N 2O2)(PPh3)] abbreviated as [CuBrLPPh 3] (1) and [CuILPPh3] (2) (L = 1,10-phenanthroline-5,6- dione). Nonlinear optical properties of the complexes are investigated at 532 nm using single beam Z-scan and degenerate four-wave mixing (DFWM) techniques employing nanosecond laser pulses. The complexes show optical limiting behaviour due to "effective" two-photon absorption. The values of the effective two-photon absorption (2PA) coefficients (?), third-order nonlinear susceptibilities (?(3)), and figures of merit (F), are calculated. © 2010 Elsevier B.V. All rights reserved.Item A rapid extractive spectrophotometric determination of copper(II) in environmental samples, alloys, complexes and pharmaceutical samples using 4-N,N(dimethyl)amino]benzaldehyde thiosemicarbazone(2011) Karthikeyan, J.; Naik, P.P.; Nityananda Shetty, A.N.4-[N,N-(Dimethyl)amino]benzaldehyde thiosemicarbazone (DMABT) is proposed as an analytical reagent for the extractive spectrophotometric determination of copper(II). DMABT forms yellow colored complex with copper(II) in the pH range 4.4-5.4. Beer's law is obeyed in the concentration range up to 4.7 ?g mL -1. The optimum concentration range for minimum photometric error as determined by Ringbom plot method is 1.2-3.8 ?g mL-1. The yellowish Cu(II)-DMABT complex shows a maximum absorbance at 420 nm, with molar absorptivity of 1.72 × 104dm3 mol-1 cm-1 and Sandell's sensitivity of the complex obtained from Beer's data is 0.0036 ?g cm-2. The composition of the Cu(II)-DMABT complex is found to be 1:2 (M/L). The interference of various cations and anions in the method were studied. Thus the method can be employed for the determination of trace amount of copper(II) in water, alloys and other natural samples of significant importance. © 2010 Springer Science+Business Media B.V.Item Application of Prigogine-Flory-Patterson theory to volumetric, ultrasonic, and compressibility parameters of (glycylglycine + CuCl2) in aqueous ethanol mixtures(2011) Santosh, M.S.; Bhat, D.K.The molar volume and compressibility of (glycylglycine + CuCl2) in aqueous ethanol mixtures have been obtained at four different temperatures T = (288.15 to 318.15) K from ultrasonic velocity and density measurements. Excess molar volumes were found to be negative throughout the composition range indicating notable changes in hydrogen bonding and electrostatic interactions. Using the Prigogine-Flory-Patterson theory, quantitative estimation of different contributions, i.e. interactional, free volume, and P effect to VE have been obtained. The molar isentropic compressibility has been computed using the ultrasonic velocity and excess volume data. The trends in ?SE are affected by the size of the molecule leading to negative contributions. In order to compare the theoretical values of ultrasonic velocity, the equations of Nomoto and Junjie were used and found to predict the experimental data very well. © 2011 Elsevier Ltd. All rights reserved.Item Synthesis of copper nanofluids using ascorbic acid reduction method via one step solution phase approach(ASTM International, 2012) Shenoy, S.U.; Nityananda Shetty, A.N.A simple one step solution phase approach to synthesize copper nanofluids has been developed, involving simultaneous in situ synthesis of nanoparticles and their dispersion in the base fluid. Copper nitrate has been reduced using ascorbic acid in ethylene glycol under thermal as well as microwave conditions. Sodium lauryl sulfate has been used to control the size of the particle as well as to act as a stabilizing agent. The effect of ratio of the reactants, pH, power of microwave, reaction time, and dilution on the size of the particles has been studied using X-ray diffraction, transmission electron microscopy, and field-emission scanning electron microscopy. The characterization of the fluids has also been done using Fourier transform infrared spectrometry, ultraviolet-visible spectroscopy, selected area electron diffraction, and energy dispersive X-ray analysis. The thermal conductivity and viscosity of the fluid were also measured at various particle concentrations. The copper particles in the fluid were found to have size less than 50nm and were well dispersed in the fluid. Thus this method was found to preserve the advantages of the polyol process and aqueous chemical reduction method as well. The fluid was stable up to 5 weeks under stationary conditions at room temperature. This method employs fast, inexpensive, extendible process for the synthesis of copper nanofluids and also overcomes the drawbacks of two step process. Copyright © 2012 by ASTM International.Item Synthesis and characterization of schiff base metal complexes and reactivity studies with malemide epoxy resin(Korean Chemical Society sunlee@kcsnet.or.kr, 2012) Lakshmi, B.; Shivananda, K.N.; Prakash, G.A.; Isloor, A.M.; Mahendra, K.N.A novel malemide epoxy containing Co(II), Ni(II) and Cu(II) ions have been synthesized by curing malemide epoxy resin (MIEB-13) and Co(II), Ni(II) and Cu(II) complexes of macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting 1,4-dicarbnyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol. The Schiff base and its Co(II), Ni(II) and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, 1H NMR, UV-vis., FAB mass, ESR), thermal and magnetic data. The curing reaction of maleimide epoxy compound with metal complexes was studied as curing agents. The stability of cured samples was studied by thermo-gravimetric analyses and which have excellent chemical (acid/alkali/solvent) and water absorption resistance. Further, the scanning electron microscopy (SEM) and definitional scanning colorimetric (DSC) techniques were confirmed the phase homogeneity of the cured systems.Item Microstructural characterization and hardness evaluation of friction stir welded composite AA6061-4.5Cu-5SiC (Wt.%)(Defense Scientific Information and Documentation Centre, 2013) Shettigar, A.K.; Salian, G.; Herbert, M.A.; Rao, S.Recent developments in advanced materials research have led to the emergence of new materials having features like low density, high strength to weight ratio, excellent mechanical properties, heat and corrosion resistance. In friction stir welding (FSW), a non-consumable rotating welding tool is used to generate the frictional heat and plastic deformation of the material in the welding zone, which is in the solid state. The advantages of FSW as compared to the fusion welding are high joint strength, less defect weld, uniform distribution of grain structure in the weld zone and low power consumption. AA6061 with 4.5 % weight of copper and 5 % weight of SiC composite material has been prepared to conduct experiment and carry out characterization, evaluation of the mechanical properties. Micro-structural characterization of the weld zone is carried out by scanning electron microscope (SEM). Evaluation of hardness was also carried out across the weld zone. A successful method for FSW of AA6061-4.5(wt.%) Cu-5(wt.%) SiC has been developed. © 2013, DESIDOC.Item Spreading behavior and evolution of IMCs during reactive wetting of SAC solders on smooth and rough copper substrates(2013) Satyanarayan, S.; Prabhu, K.The effect of surface roughness of copper substrate on the reactive wetting of Sn-Ag-Cu solder alloys and morphology of intermetallic compounds (IMCs) was investigated. The spreading behavior of solder alloys on smooth and rough Cu substrates was categorized into capillary, diffusion/reaction, and contact angle stabilization zones. The increase in substrate surface roughness improved the wetting of solder alloys, being attributed to the presence of thick Cu 3Sn IMC at the interface. The morphology of IMCs transformed from long needle shaped to short protruded type with an increase in the substrate surface roughness for the Sn-0.3Ag-0.7Cu and Sn-3Ag-0.5Cu solder alloys. However, for the Sn-2.5Ag-0.5Cu solder alloy the needle-shaped IMCs transformed to the completely scallop type with increase in the substrate surface roughness. The effect of Ag content on wetting behavior was not significant. © 2013 TMS.