Two novel mononuclear five-coordinate nickel complexes with distorted square-pyramidal geometries are presented. They result from association of a tridentate "half-unit" ligand and 6,6'-dimethyl-2,2'-bipyridine according to a stepwise process that highlights the advantage of coordination chemistry in isolating an unstable tridentate ligand by nickel chelation. Their zero-field splittings (ZFS) ...

BACKGROUND Fixed orthodontic appliances with the use of stainless steel brackets and archwires made of nitinol have a corrosive potential in the oral environment. Nickel and chromium ions released from these appliances act as allergens apart from being cytotoxic, mutagenic and carcinogenic in smaller quantities in the range of nanograms. This study was done to evaluate the release of nickel and...

lead, copper, cobalt, nickel, iron and zinc ions form monocitrate complexes (negative charge) in citrate solution which is absorbed on the citrate form of anion-exchange resins (citrate as counter ion) y exchange of citrate ion with citrate complexes. these are subsequently recovered from the resin by 0.5m ammonium citrate eluent at ph 2.0. under optimized conditions, quantitative recovery was ...

OBJECTIVES The aims of this study were to quantify the metallic ions released by various dental alloys subjected to a continuous flow of saliva and to estimate the nutritional and toxicological implications of such a release. METHODS Four pieces of three nickel-based, one noble, one high-noble and two copper-aluminum alloys were cast and then immersed in a continuous flow of artificial saliva...

Lead, copper, cobalt, nickel, iron and zinc ions form monocitrate complexes (negative charge) in citrate solution which is absorbed on the citrate form of anion-exchange resins (citrate as counter ion) y exchange of citrate ion with citrate complexes. These are subsequently recovered from the resin by 0.5M ammonium citrate eluent at pH 2.0. Under optimized conditions, quantitative recovery ...

in this study, aniline-formaldehyde polymer was synthesized and then modified with extra aniline as cross-linker in the presence and absence of ni(ii) as the template to produce ion imprinted poly(aniline-formaldehyde) (iipaf) and non imprinted poly(aniline-formaldehyde)(nipaf) the iipaf was subjected to adsorption, preconcentration and determination of ni(ii) ion in environmental samples. the ...

Nickel Cadmium batteries are popular because they have a relatively low cost and offer a mature technology. Nickel Metal Hydride batteries have improved volumetric efficiency and have less environmental concerns than Nickel Cadmium. Lithium-Ion batteries are emerging as a leader in the portable market due to their high energy density. Lithium-Ion batteries have the highest initial cost, however...

Experimental data on cadmium (II) and nickel (II) ion sorption on deactivated protonated yeast over a wide range of sorbent and initial metal concentrations, were analyzed by an equilibrium model based on a thermodynamics approach. Model describes relationships between the equilibrium concentration of metal, metal sorption per unit biomass dosage and concentration of sorbent and initial metal c...

Nickel homeostasis is important for pathogenic and ureolytic bacteria, which use this metal ion as enzymatic cofactor. For example, in the human pathogen Helicobacter pylori an optimal balance between nickel uptake and incorporation in metallo-enzymes is fundamental for colonization of the host. Nickel is also used as cofactor to modulate DNA binding of the NikR regulator, which controls transc...