The syn theses of diaquabis (3-hydroxyflavonato) cobalt (II) and bis(pyridine) bis (3hydroxyflavonato)cobalt(II) are described. Results from infrared spectra clearly show that the 3-hydroxyflavonato anion forms a chelate through the 3-hydroxy 4-keto groups. The electronic spectra of both complexes indicate that cobalt(II) has an octahedral geometry. Quantitative analyses of the isolated product...

Nickel and cobalt sulfides are promising materials in different cutting-edge research areas like solar cells, supercapacitors, catalysts, and electrode materials. Nickel and cobalt sulfides with various stoichiometries have been synthesized sonochemically from Ni(CH3COO)2 ∙ 4H2O, Co(CH3COO)2 ∙ 2H2O and different sulfur precursors using a direct immersion ultrasonic probe. The products were char...

Nickel and cobalt (Ni-Co) binary oxide nanosheets with mesoporous structure are prepared by a facile approach based on the formation and disassociation of nickel/cobalt-citrate complex, and they show an ultra-high Faradaic capacitance up to 1846 F g(-1) and excellent rate capability. On this basic, advanced aqueous asymmetric supercapacitors (AASs) are successfully built by using the Ni-Co oxid...

The effects of nickel, cobalt, chromium and zinc on the content of vitamins A, E and C, malondialdehyde (MDA), chlorophyll and carotenoids were investigated in bean seedlings (Phaseolus vulgaris L.) grown in Hoagland solution Control and heavy metal-treated plants were grown for ten days in Hoagland solution. Vitamin A, E, and C content were measured in primary leaves by high performance liquid...

OBJECTIVES To assess the exposure to tungsten, cobalt, and nickel in a plant producing hard metals. The main components of hard metals are tungsten carbide and cobalt metal. According to recent studies, these two components may be responsible for both fibrogenic and carcinogenic effects. METHODS 87 workers were investigated (86 male, one female) with a median age of 42 (range 22-58) and a mea...

The conversion of acetic acid to methane and carbon dioxide by a mixed methanogenic population from an anaerobic fixed-film digestor was stimulated by the addition of nickel (100 nM) and cobalt (50 nM) and especially by the addition of these elements in combination. Molybdenum addition (50 nM) was only slightly stimulatory when added in combination with both nickel and cobalt. The addition of t...

Rene88 samples were investigated using atom probe tomography and x-ray diffraction using a monochromated synchrotron beam with different energy values to determine the preferred site occupancy of various alloying elements within the ordered γ’ precipitates. Samples were solutionized and cooled at 24 degree C/min with subsequent aging at 760 degrees C. The synchrotron-based x-ray diffraction res...

Cosmetics should not contain more than 5 ppm of nickel, chromium or cobalt and, in order to minimize the risk of sensitization in very sensitive subjects, the target amount should be as low as 1 ppm. However, there are no published reports on the presence of these metals in toy make-up. This study analysed 52 toy make-ups using atomic absorption spectroscopy. More than 5 ppm of nickel was prese...

Cobalt oxide films were prepared by electrochemically precipitating the hydroxide and heating it in air to form Co3O4. The resulting oxide films behave as a capacitor. The materials were studied emphasizing their use as either positive or negative electrodes in devices. The capacitance of the material was estimated at different heating temperatures and insight was gained into the charge storage...

In this article, we present a facile and low-cost method to prepare urchin-like nickel-cobalt carbonate hollow spheres that display excellent electrooxidation of nitrite. The as-fabricated samples are characterized by XRD, SEM, TGA, and BET. The results confirm that the successful formation of nickel carbonate and cobalt carbonate at ratio of 1/2, and their entirely uniform hollow microspherica...