When Streptomyces sp. strain Wak. A-305 is cultured in iron (III)- or cobalt (II)-containing media, tris(p-vinylphenyl-4-hydroxy-3-nitrosobenzoato-N3, O4)ferrate(II) (ferroverdin) or the analogous tris-cobalt(III) complex, respectively, is produced intracellularly. In contrast, when cultured in transition metal ion-limiting media. Streptomyces sp. strain Wak. A-305 did not produce p-vinylphenyl...

A self-assembly reaction between the ditopic ligand 4,5-bis(tetrazol-5-yl)imidazole (H3IBT) and cobalt(II) chloride in basic aqueous medium afforded the mixed-valence molecular species ðNBu4Þ141⁄2Co III 6Co II 2ðIBTÞ12 22H2O (1). X-ray analysis of 1 revealed a cubic arrangement of six trivalent and two divalent cobalt ions, with the latter situated on opposing vertices along the cube diagonal. ...

B. P. Baranwal*, S. S. Das, Poonam Singh Chemistry Department, University of Gorakhpur, Gorakhpur 273009 India Z. Naturforsch. 52b, 1039-1042 (1997); received July 7, 1997 Cobalt(II) Derivatives, Cyclic Phosphazenes, IR Spectra Chlorine atoms of hexachlorocyclotriphosphazene were substituted with -NH.C2H5, -NH.CH 2C6H5 and -O C 2Hs to yield organotriphosphazene ligands. Anhydrous cobalt(II) chl...

Metal-dioxygen adducts are key intermediates detected in the catalytic cycles of dioxygen activation by metalloenzymes and biomimetic compounds. In this study, mononuclear cobalt(III)-peroxo complexes bearing tetraazamacrocyclic ligands, [Co(12-TMC)(O(2))](+) and [Co(13-TMC)(O(2))](+), were synthesized by reacting [Co(12-TMC)(CH(3)CN)](2+) and [Co(13-TMC)(CH(3)CN)](2+), respectively, with H(2)O...

In this work, the development of a tryptophan sensor and its application to milkare described. The mixed metal (copper and cobalt) hexacynoferrates are electrodepositedon the graphite electrode, and this film exhibits an electrocatalytic activity towards for theoxidation of tryptophan. The experimental conditions, including the scan cycles, the ratio ofcopper(II) and cobalt(II), pH value, appli...

A lignocellulose/montmorillonite (LMT) nanocomposite was prepared as a reusable adsorbent for cobalt(II) ions, and characterized by nitrogen (N₂) adsorption/desorption isotherm, X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), and Fourier Transform Infrared Spectroscopy (FTIR). LMT exhibited efficient adsorption of cobalt ions (Co(II)), and th...

Although cobalt is an essential trace element, it is toxic in high concentrations. Long-term exposure to cobalt chloride (CoCl2) significantly increases Co(II) ions in blood serum, spleen and liver of treated immature mice compared to controls and induces changes in the iron (Fe) content. Spleen and liver show different sensitivity to Co(II) administration but increase iron storage. The three e...

Synthesis, identification and thermal behavior studies of nanoparticles cobalt (II) bromide has been studied in this research. Cobalt (II) bromide was synthesized by planetary high-energy ball mill. The general formula of this compound is CoBr2.6H2O. The synthesized nanoparticles were characterized by Fourier transform infrared spectroscopy and also Size and structure of s...

Cobalt oxide (Co3O4) nanoparticleshave been synthesized by hydrothermal method using mixture of cobalt(II)chloride, Triton X-100 and KOH in an autoclave at 180 °C for 6 h followed by heating at 400 ºC for 3 h in air. The product have been characterized by Fourier transform infrared (FT-IR), UV-Vis spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission ...

Cobalt(II) compounds [Co(C10C8C2-terpy)2](BF4)2 (1) and [Co(C12C10C2terpy)2](BF4)2 (2) (CxCyCz-terpy = 4’-5’’’-Alkyl-1’’’-alkoxy-2,2’:6’,2’’-terpyridine) with branched alkyl chains, based on a terpyridine frame, were synthesized. The cobalt(II) compounds 1 and 2 exhibit the spin transition between low-spin and high-spin with thermal hysteresis loop at the liquid crystal transition temperature (...