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The present work reports a soft chemical approach for synthesis of nanostructured W 10–20 wt.% Ti alloys and its characterization. Though, the as-prepared products are amorphous, they developed crystalline phases when annealed at 600 °C due to the presence of bcc and hcp structure of W and Ti respectively. ESEM and TEM studies show that the sizes of as-synthesized powders ranged between 30 and 50 nm. W-10–20 wt.% Ti alloys, when sintered at 1400 °C for 1 h, exhibit relative density, Vickers hardness and electrical resistivity varying between 98.4–99.1%, 506–595 Hv and 6.28–7.43 μΩ-cm respectively. [ABSTRACT FROM AUTHOR]

W–Mo nanoalloys of variable compositions with average sizes ~ 40 nm were synthesized using a single step soft chemical approach in presence of l -cysteine. FTIR study reveals that l -cysteine binds to the surface of W–Mo nanoalloys via a thiolate linkage, which renders stability with respect to aggregation and growth. As-synthesized W–Mo alloys are found to be amorphous and bcc crystalline peaks developed on annealing at 600 °C. In addition, the effect of nanoscale particles on densification behavior of W–Mo alloy has also been investigated. The relative density of W–19.9 wt.% Mo, W–30.4 wt.% Mo and W–40.2 wt.% Mo alloy compacts sintered at 1600 °C is maximum achieved corresponding to 97.5, 98.1 and 98.9 % respectively. Further, superior Vickers hardness has been achieved in the sintered specimens compared to those obtained from microcrystalline or mechanically alloyed powders. [ABSTRACT FROM AUTHOR]

Abstract: In the present investigation, W;40wt.% Cu nanocomposite powders with average sizes ranging between 25 and 30nm were synthesized by a soft chemical approach using tungsten hexacarbonyl [W(CO)6] and copper acetonyl acetonate [Cu(acac)2] as metal precursors. Particle size, morphology and distribution were measured using transmission electron microscope (TEM) and small angle X-ray scattering (SAXS). Surfactant coating on Wite powders was removed on heat treatment of powders at 450°C in hydrogen atmosphere for 1h. Elemental analyses of as-synthesized and annealed (at 450°C) Wmposite powders were carried out using inductively coupled plasma-optical emission spectrometer (ICP-OES) and Leco gas analyzers. X-ray diffraction studies showed that the tungsten phase is amorphous while the crystal structure of copper phase is fcc in as-synthesized Wmposite powders. After annealing at 700°C peaks corresponding to bcc tungsten are observed and peaks corresponding to fcc copper become sharper. Relative densities of 98.2%, 98.8% and 99.2% were achieved for W, W, and W composite powders respectively when sintered at 1000°C. [Copyright &y& Elsevier]

Abstract: A series of novel ketoprofen derivatives 4a–j bearing both amide and carbamate functionalities were prepared using benzotriazole. Selective reduction of ketoprofen produced hydroxy derivative 2, which reacts with one or 2 mol of 1-benzotriazole carboxylic acid chloride (1) gave benzotriazole derivatives 3a and 3b respectively. Antioxidative screenings revealed that the prepared compounds 3b and 4a–j possess excellent lipid peroxidation inhibition at 0.1 mM concentration. Two of the compounds 3b and 4g also showed high soybean lipoxygenase inhibition activity, where as the amidocarbamate derivatives of ketoprofen showed only weak reducing activity against 1,1-diphenyl-2-picrylhydrazyl radicals. No selective antiviral effects were noted for the tested compounds against a broad variety of DNA and RNA viruses. [Copyright &y& Elsevier]

Abstract: The acetic acid derivatives of [1,2,4]triazino[4,3-a]benzimidazole (TBI) were synthesized and tested in vitro and in vivo as selective aldose reductase (ALR2) inhibitors. Compound PS11 showed highest inhibitory activity (IC50) 0.32μM and was found to be effective in preventing cataract development in severely galactosemic rats when administered as an eyedrop solution. All the compounds investigated were selective for ALR2, since none of them inhibited appreciably aldehyde reductase, sorbitol dehydrogenase, or glutathione reductase. [Copyright &y& Elsevier]

Abstract: Tungsten nanoparticles were prepared by thermal decomposition of tungsten hexacarbonyl [W(CO)6] (2mmol) at 160°C in presence of a mixture of (1:1) surfactants, oleic acid (6mmol) and trioctyl phosphine oxide (TOPO) (6mmol) under a blanket of Ar gas. The synthesized tungsten nanoparticles without surfactant are flocculated. With increase in concentration of surfactant mixture to 12mmol each, agglomeration of several tungsten nanoparticles are observed. Characterization of surfactant coated tungsten nanoparticles were carried out using Fourier transform infrared spectroscopy (FTIR). Chemical characterizations of synthesized tungsten nanoparticles were done using X-ray photoelectron spectroscopy (XPS), inductively coupled plasma-optical emission spectrometry (ICP-OES) and LECO gas analyzers. XPS study shows the W0 oxidation state of tungsten nanopowders. Structural characterization of synthesized tungsten nanoparticles were conducted by X-ray diffraction (XRD), which shows that the as-synthesized tungsten nanoparticles are amorphous in nature and they become body centered cubic crystalline after annealing. Particle size, shape and distribution were characterized using small-angle X-ray scattering (SAXS), environmental scanning electron microscopy (ESEM) and transmission electron microscopy (TEM). [Copyright &y& Elsevier]

A modified polyol process in conjunction with a transmetallation reaction was employed for the synthesis of Co36.6Ag63.4 core-shell nanocomposite. TEM micrographs reveal the existence of core-shell structure with an average cobalt core size of 8.5nm. As-synthesized sample exhibited a superparamagnetic behavior at room temperature. Magnetoresistance measurements carried out on pelletized sample revealed an optimal value of 3.6% at 5K. [ABSTRACT FROM AUTHOR]