Many of the silver deposits on which there is seemingly general agreement as to their hypogene (primary) origin, and particularly those deposits in which native silver is a fairly common constituent, show a characteristic association of nickel and cobalt arsenides with native silver or other silver minerals. In view of the generally recognized hypogene origin of the nickel and cobalt arsenides ...

Composite chitosan-magnetite microparticles (Fe-Cc) were evaluated as a new adsorbent for cobalt and nickel ion separation from aqueous solutions. Sorption batch experiments were conducted for optimizing the pH, initial target ion concentration and adsorbent amount. The experimental data were fitted using Langmuir, Freundlich, and respectively DubininRadushkevich isotherm models. The Langmuir m...

The effect of metal particles on the photoluminescence (PL) and the Raman spectra of functionalized SWCNTs in aqueous solutions was systematically investigated by studying three different metal particles (gold, cobalt, and nickel) on three different SWCNT suspensions (DNA-, RNA-, and sodium deoxycholate salt (DOC)-functionalized SWCNTs). Substantial enhancement of the PL intensities was observe...

The Costa Rica upwelling dome (CRD; ;8.678N and 90.68W) was characterized chemically for cobalt and nickel abundances and speciation and biologically using cyanobacterial abundances and phylogeny. Total dissolved cobalt was 93 pmol L21 at 90 m depth and decreased in surface waters to 45 pmol L21 at 10 m. Cobalt was 40% labile at 90 m but was completely complexed by strong ligands at 10 m. A sur...

In the current work, we demonstrate how coordination chemistry can be employed to direct self-assembly based on strong hydrophobic interactions. To investigate the influence of coordination sphere geometry on aqueous self-assembly, we synthesized complexes of the amphiphilic perylene diimide terpyridine ligand with the first-row transition-metal centers (zinc, cobalt, and nickel). In aqueous me...

A rapid flotation method for separation and enrichment of ultra trace amounts of copper(II), cadmium(II), nickel(II) and cobalt(II) ions from water samples is established. At pH 6.5 and with sodium dodecylsulfate used as a foaming reagent, Cu2+, Cd2+, Ni2+ and Co2+ were separated simultaneously with 2-aminocyclopentene-1-dithiocarboxylic acid (ACDA) added to 1 l of aqueous solution. The propose...

Aluminium-silicon alloys have gained increasing market share in the automotive and aerospace industry because of increased environmental demands. These alloys have a high strength-to-weight ratio, good corrosion resistance, castability and recycling potential. However, variations in properties and limited performance at elevated temperature are restricting these alloys from use at elevated temp...

OBJECTIVES Evaluation of the allergenic properties of the metal knee or hip joint implants 24 months post surgery and assessment of the relation between allergy to metals and metal implants failure. MATERIALS AND METHODS The study was conducted in two stages. Stage I (pre-implantation) - 60 patients scheduled for arthroplasty surgery. Personal interview, dermatological examination and patch t...

It is well-known that nanoparticles could cause toxic effects in cells. Alloy nanoparticles with yet unknown health risk may be released from cardiovascular implants made of Nickel-Titanium or Cobalt-Chromium due to abrasion or production failure. We show the bio-response of human primary endothelial and smooth muscle cells exposed to different concentrations of metal and alloy nanoparticles. N...

OBJECTIVES To determine the prevalence of metal contact allergy among the children seen at a health center children with metal allergies in terms of risk factors. METHODS This was an uncontrolled cross-sectional study undertaken at a health center in Belo Horizonte, Brazil. Children aged from 0 to 12 years were recruited when they presented at the health center for routine pediatric consultat...