Monopyridineiodine(I) chloride in ethanol as a new iodinating reagent for metal <em>β</em>-diketones and ketoneimines

702-703A direct iodination procedure is described for the introduction of iodine in the 3-position of the metal β-diketonates of Cr(III), Co(III), AI(III), Be(II), oxovanadium(IV), Ni(II) and Cu(II) employing monopyridine iodine(I) chloride in ethanol or methanol medium as a new iodinating reagent for β-diketonates. Unlike the reagents known already, monopyridineiodine(I) chloride gamma-iodinates at room temperature (in 10 min) giving 75-90% yield. On iodination, Ni(bzac)2 changes from the high spin to a low spin state due to steric factors. 3-Iodovandylacetylacetonate has been prepared for the first time using the present reagent

Synthesis and characterization of copper(ll), nickel(ll), oxovanadium(IV), manganese(ll), zinc(ll), cadmium(ll), mercury(ll), zirconyl(IV) and dioxouranium(VI) complexes of 3-salicylideneacetylacetonediimino N,N-bis( anthranilic acid)

919-921A few metal complexes of Cu(II), Ni(II), Cu(II), oxovanadium(IV), Mn(II), Zn(II), Cd(II), Hg(II), ZrO(II) and dioxouranium(VI) ions with a new tetradentate schiff base derived from 3-salicylideneacetylacetone and anthranilic acid have been synthesized and characterized. The IR, UV and magnetic data suggest a six-coordinate octahedral geometry for the complexes

Synthesis, spectral, redox and biological studies of some Schiff base copper(II), nickel(II), cobalt(II), manganese(II), zinc(II) and oxovanadium(II) complexes derived from 1-phenyl-2,3-dimethyl-4(4-iminopentan-2-one)pyrazol- 5-one and 2-aminophenol/2-aminothiophenol

942-949Neutral tetradentate complexes of Cu(II), Ni(II), Co(II), Mn(II), Zn(II) and VO(II) have been synthesised using new Schiff bases derived from 2-am inophenol/2-aminothiophenol and 1-phenyl-2,3-dimethy l-4(4-iminopentan-2-one)-pyrazol -5-one in ethanol and characterized by microanalytical data, IR, UV -Vis .. 1H NMR and ESR spectra. Non-electrolytic behaviour and monomeric type of the chelates have been assessed from their 10Vl conductance and magnetic susceptibility values respectively. The IR and UV-Vis. spectra suggest that all the complexes have square planar geometry except vanadyl and manganese complexes which show square pyramidal and octahedral geometry respectively. The redox behaviour of copper and vanadyl complexes has been studied by cyclic voltammetry and the ESR spectra of copper and vanadyl complexes are recorded and discussed. Antimicrobial act ivity of the Schiff bases and their complexes have been extensively studied on some microorganisms like Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Salmonella, typhi, Pseudomonous aeruginosa, Shigella flexneri, Aspergillus niger and Trichoderma viridi. Most of the complexes have higher activity than the free ligand

Investigation on the Electrical Properties of Polymer metal Nanocomposites for Physiological Sensing Applications

AbstractCopper nanoparticles were prepared by Polyol Method and the prepared metal nanoparticles were characterized by various techniques like AFM, SEM, FTIR Spectrum and XRD. The prepared metal nanoparticles are used to improve the electrical conductivity of dielectric polymers like PMMA. Polymer Metal Nanocomposite was prepared by in-situ oxidative polymerization of Methylmethacrylate monomer in the presence of different concentration of prepared metal nanoparticles. The formation of the polymer metal nanocomposites was characterized by UV-Vis Spectroscopy, SEM and AFM. The electrical conductivity was investigated using Four-Point Probe Techniques and the conductivity value of the PMMA/Cu nanocomposite was in the range of mS/cm. The conductivity of the dielectric polymer was found to be increased with the increasing metal concentration. The prepared nanocomposite can be used to convert the insulating foam into conductive one which can be used to fabricate wearable sensors for physiological (Breath Rate, Limb Movement, etc.,) monitoring

Enhanced near-infrared reflectance and functional characteristics of nano metal oxide embedded alkyd coatings

The main idea of the research is to formulate alkyd based smart coatings with high NIR-reflectance to decrease the cooling load in order to maintain cool comfort in buildings. In addition to the NIR reflectance studies, the physical characteristics of the coating such as glossiness, hiding power, spreading area, volatile organic contents are evaluated. Heat reflective coatings are prepared by ball milling technique utilizing white metal oxide nanoparticles (NPs) titanium oxide (TiO _2 ), zinc oxide (ZnO) and zirconium oxide (ZrO _2 ) as pigments. The x-ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) results reveal the prepared metal oxide pigments are of high purity. Bonding interaction between the alkyd resin and the NPs are studied using Fourier transform infrared spectroscopy (FTIR).The spectral reflectance of the prepared coatings are measured using spectrophotometer in the solar spectrum range, wherein ZnO based nanocoatings shows better results. The cool comfort is measured for ZnO nanocoatings in an enclosed glass cabinet and the differences in temperature with respect to exposure to sunlight are highlighted. Finally, a prototype coated with ZnO NPs maintains lower indoor temperature than the commercially available white paint coated model in the order of 2.7 °C

Synthesis and structural characterization of Cu(II) and Ni(II) complexes of antipyrine schiff base derivatives

147-150The terfunctional schiff base ligands acetylaceton-4aminoantipyrine, salicylal-4-aminoantipyrine and 2-hydroxy-1-naphthal-4-aminoantipyrine react with Cu(II) and Ni(II) metal ions in different stoichiometric ratios and at various pH values to yield complexes with different bonding features such as (i) neutral bidentate - coordination via. > C = 0 and > C = N-, (ii) neutral terdentate - coordination via. > C=O, =CH-NH- and quinonoid = O: from -OH, (iii) monovalent bidentate - coordination via. > C = N-, and -O- from -OH and (iv) monovalent terdentate coordination via. > C = N, > C = O and -O- from -OH

Photochemical and thermal bromination of metal acetylacetonates by pyridinium bromochromate in acetic acid medium

623-624Photochemical and thermal brominations of metal β-diketonate complexes of Mn(II), Co(II), Cu(II), Zn(II), Cr(III), Mn(III), Fe(III), Co(III), Ce(IV), Th(IV) and UO2(VI) by pyridinium bromochromate (PBe) in glacial acetic acid have been carried out. Under ambient conditions, the tris and tetrakis chelates underwent electrophilic γ-bromination whereas the bis-chelates decomposed yielding bromo complexes by nucleophilic addition of bromine. Under photo irradiation λ = 254 or λ = 357 nm except those of Cr(III), Ce(IV) and Th(IV) complexes which underwent electrophilic λ-substitution, all the other complexes decomposed forming bromo complexes

Zinc oxide nanoparticles as photo-catalytic and anti-bacterial pigment for alkyd resin based coating

Purpose: Recently, there has been an upsurge among people around the world in maintaining a sustainable and hygienic environment. This is due to the over-exploitation of recourses causing environmental pollution and spreading bacterial infections. In this regard, scientists are motivated to develop smart coatings where environmental pollutants and bacterial cells are degraded when in contact with their surfaces. Design/methodology/approach: In our previous report, ZnO nanoparticles (NPs) were prepared using the precipitation technique, showing good photocatalytic and antibacterial activity [1]. In this context, the present study details the use of ZnO NPs as pigment for the fabrication of alkyd resin-based self-cleaning coating. The coating was developed by mixing ZnO NPs and alkyd resin along with the additives using the ball milling technique. The developed coating was characterized using field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, atomic force microscopy, and water contact angle measurements. Findings: To elucidate the self-cleaning and hygienic behaviour of the ZnO/alkyd resin coating, the dried coating was exposed to crystal violet (CV) solution as a model dye pollutant and bacterial strains to assess its photocatalytic and antibacterial activity. The droplets of CV solution placed over the coating almost degraded after 360 min of exposure to sunlight owing to the presence of ZnO NPs in the coating. Further, the coating exhibits reasonable antibacterial activity against E. coli and P. aeruginosa whereas it displays low antibacterial activity against S. aureus. Research limitations/implications: Even though, the self-cleaning coating shows promising results, tuning the activity of the photo-catalytic pigment can improve the pollutant degradation efficiency and elevate bactericidal activity. Originality/value: ZnO NPs-impregnated alkyd resin coating for self-cleaning applications is novel