Cobalt is a nutrient to phytoplankton, but knowledge about its biogeochemical cycling is limited, especially in the Pacific Ocean. Here, we report sections of dissolved cobalt and labile dissolved cobalt from the US GEOTRACES GP16 transect in the South Pacific. The cobalt distribution is closely tied to the extent and intensity of the oxygen minimum zone in the eastern South Pacific with highes...

The effect of cobalt precursor on the structure of Co supported multi-walled carbon nanotubes (MWCNTs) were studied by using X-ray photoelectron spectroscopy (XPS). MWCNTs were treated with a mixture of nitric and sulfuric acids and decorated with cobalt and/or cobalt oxides via aqueous impregnation solutions of cobalt nitrate or cobalt acetate followed by reduction in hydrogen. XPS was mainly ...

the potential of carbon nanotubes (cnt) supported cobalt catalysts for fischer-tropsch (ft) reaction is shown. using the wet impregnation method cobalt on carbon nanotubes catalysts were prepared with cobalt loading varying from 15 to 45 wt. %. the catalysts are characterized by different methods including: bet physisorption, x-ray diffraction, hydrogen chemisorption, and temperature-programmed...

A new chemiluminescence method is proposed for the determination of sulfide in seawater based on the chemiluminescence reaction between sulfide and an acidic permanganate solution. 3-Cyclohexylaminopropanesulfonic acid was used as a chemiluminescence enhancer. By use of this method, 1-150 µM of sulfide could be determined in artificial seawater. The limit of detection was 0.17 µM sulfide. We in...

The measurement of sulfide, especially hydrogen sulfide, has held the attention of the analytical community due to its unique physiological and pathophysiological roles in biological systems. Electrochemical detection offers a rapid, highly sensitive, affordable, simple, and real-time technique to measure hydrogen sulfide concentration, which has been a well-documented and reliable method. This...

Cobalt(iii) complexes [Co(pnt)(B)(2)](NO(3))(2) (1-3) of pyridine-2-thiol (pnt) and phenanthroline bases (B), viz. 1,10-phenanthroline (phen in 1), dipyrido[3,2-d:2',3'-f]quinoxaline (dpq in ) and dipyrido[3,2-a:2',3'-c]phenazine (dppz in 3), have been prepared, characterized and their photo-induced anaerobic DNA cleavage activity studied. The crystal structure of 1a as mixed ClO(4)(-) and PF(6...

Recent advances in nanotechnology could facilitate the production of cheaper solar cells. This review describes synthetic routes to various nanostructured materials that are potentially useful in photovoltaic applications. We have focused on materials that are based on earth abundant elements and/or those that are held to have lower toxicity. Methods to synthesize binary chalcogenides with vari...

We study the interaction of circumcoronene molecule C54H18 with cobalt in the form of atoms, dimers and clusters of four atoms. We find that the cobalt atom prefers to be on a hollow site in the edge zone. The cobalt dimer is bonded perpendicularly to another different hollow site in the edge zone. The Co4 cluster adopts a tetrahedral shape with a face parallel to circumcoronene, placing each o...

Fischer-Tropsch synthesis is a part of Gas-to Liquids (GTL), Biomass-to-Liquids (BTL) and Coal to Liquids (CTL) technologies, which produce alternatives clean fuels from natural gas, biomass and coal. The catalytic performance of cobalt catalysts in Fischer-Tropsch synthesis strongly depends on the size of cobalt particles in nanoscale range (6-30 nm). Cobalt catalysts are usually prepared via ...

cobalt is an essential co-factor in red blood cell production and function and its deficiency may produce clinical signs in sheep. thus, present study was designed to evaluate the effect of cobalt nano-particles on serum biochemical factors and histopathological changes in liver and kidnies of lambs. study was carried out in 3 groups of lambs (4 lambs per group). one group of lambs was kept as ...