Mixed-valent manganese phosphonate clusters [Mn(II)(8)Mn(III)(2)O(2)(O(3)PC(10)H(7))(4)(C(6)H(5)CO(2))(10)(py)(4)(H(2)O)(2)] (1) and [Mn(II)(4)Mn(III)(9)O(4)(OH)(2)(O(3)PC(10)H(7))(10)(C(6)H(5)CO(2))(5)(py)(8)(H(2)O)(6)] (2) are reported. Compound 1 is the first example of manganese phosphonate clusters prepared through a microwave-assisted technique. While compound 2 is obtained under ambient ...

The influence of temperature (5, 10, 22 and 30 °C) on the long-term (30 days) sorption of Mn(2+) by viable Shewanella putrefaciens was studied by FTIR and EXAFS. The additional Mn-removal capacity of these bacteria was found to result from the surface precipitation of Mn-containing inorganic phases. The chemical composition of the Mn-containing precipitates is temperature and contact-time depen...

CONTEXT Manganese (Mn) is an essential trace element but is neurotoxic at high doses. Showering with Mn-laden water has never been evaluated as a central nervous system (CNS) delivery vector for Mn, even though intranasally administered Mn in laboratory animals circumvents the blood-brain barrier and passes directly into the brain via olfactory pathways. OBJECTIVE To review the literature on ...

The characteristics of manganese and iron binding to human apotransferrin (apo-tf) have been investigated and compared in this study. Both metal ions were taken up by human apo-tf and formed complexes, with the maximum absorbances observed at 410 and 340 nm for manganese-transferrin (Mn-tf) and 465 nm for iron-transferrin (Fe-tf). Addition of manganese (1.5 µg/ml) to the reaction mixture contai...

Application of gravity and magnetic separation methods to upgrade low grade Manganese ores from Venaj Mine has been reported elsewhere. This paper discusses the results of flotation tests, as well as combination of flotation and magnetic method to concentrate fine particles (less than 150 microns) of manganese ore. Results obtained from various direct and reverse flotation tests, using differen...

The coexistence of electrical conductivity and ferromagnetism has been achieved in a reduced graphene oxide/manganese oxide hybrid (rGO-Mn) synthesized by chemical reduction of a graphene oxide and Mn(2+) (as its GO-Mn(2+) complex) using hydrazine. The rGO-Mn and GO-Mn(2+) complexes were characterized by Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray photoelectron sp...

Application of gravity and magnetic separation methods to upgrade low grade Manganese ores from Venaj Mine has been reported elsewhere. This paper discusses the results of flotation tests, as well as combination of flotation and magnetic method to concentrate fine particles (less than 150 microns) of manganese ore. Results obtained from various direct and reverse flotation tests, using differen...

Ca(2+) is an integral component of the Mn(4)O(5)Ca cluster of the oxygen-evolving complex in photosystem II (PS II). Its removal leads to the loss of the water oxidizing functionality. The S(2)' state of the Ca(2+)-depleted cluster from spinach is examined by X- and Q-band EPR and (55)Mn electron nuclear double resonance (ENDOR) spectroscopy. Spectral simulations demonstrate that upon Ca(2+) re...

OBJECTIVE To determine the relationship between biomarkers of exposure, disease and susceptibility, and early health effects and long-term diseases related to occupational manganese (Mn) exposure. DESIGN Baseline survey of a longitudinal cohort study of workers in a ferromanganese refinery. PARTICIPANTS A total of 1888 individuals (1197 men, 691 women; average seniority 15.34 years) were en...

We have prepared and characterized a few Mn (III) complexes by using a few bidentate and tridentate ligands. Spectra of the manganese (Abstract We have prepared and characterized a few Mn (III) complexes by using a few bidentate and tridentate ligands. Spectra of the manganese (III) ion in a variety of molecular environments are reported . On the basis of solution spectra, some of these co...