Electron spin resonance of Mn2+ doped in Eu2M”3 (NO3)12.24H2 O (M” = Zn, Co) single crystals has been studied at 295 and 77 K using an X-band spectrometer. The observation of resolved Mn2+ spectra in Eu2Co3(NO3)12.24H2O at 295 K have been interpreted in terms of random modulation of interaction between Mn2+ and divalent cobalt ions by the rapid spin-lattice relaxation of cobalt ions. T1 of diva...

A high heat solid-state technique was used to produce a set of phosphor Sr4La(PO4)3O:Ce3+,Tb3+,Mn2+ (Sr:Mn). In Sr4La(PO4)3O, the luminescence characteristics, resistance, and energy conversion between Ce3+ Tb3+ as well Mn2+ were thoroughly researched. Introducing activator particles can significantly increase dim green-emitting from red-emitting Mn via conversion. The color emissions might be ...

Computations and neutron diffraction experiments are used to analyse the magnetic interactions in discrete pairs of edge-linked Mn(ii)O6 octahedra.

Divalent metal ions are crucial as cofactors for a variety of intracellular enzymatic activities. Mg2+, as an example, mediates binding of deoxyribonucleoside 5'-triphosphates followed by their hydrolysis in the active site of DNA polymerase. It is difficult to study the binding of Mg2+ to an active site because Mg2+ is spectroscopically silent and Mg2+ binds with low affinity to the active sit...

Increased manganese (Mn) use in manufacturing and in gasoline has raised concern about Mn-induced parkinsonism. Previous research indicated carrier-mediated brain entry but did not assess brain efflux. Using in situ rat brain perfusion, we studied influx across the blood-brain barrier (BBB*) of three predominant plasma Mn species available to enter the brain: Mn2+, Mn citrate, and Mn transferri...

Incubation of mouse neuroblastoma cells (clone N1E-115) with Mn2+ resulted in a rapid and transient increase in cyclic GMP formation. This effect appears to be due to an increase in calcium influx because it did not occur in the absence of extracellular calcium or in the presence of verapamil, a calcium transport inhibitor. In addition, Mn2+ inhibited muscarinic receptor-mediated cyclic GMP res...

The interaction of D-xylose isomerase purified from two sources with Mn2+ and D-xylose or the competitive inhibitor xylitol has been examined by nuclear magnetic resonance. A greater paramagnetic effect of enzyme-bound Mn2+ on the alpha anomer of D-xylose than on the beta anomer was observed, providing independent evidence for the specificity of D-xylose isomerase for the alpha anomeric form of...

Stopped-flow fluorimetric studies at 37 degrees C have shown that ADP, at optimal concentrations, can evoke Ca2+ or Mn2+ influx in fura-2-loaded human platelets without measurable delay. In contrast, the release of Ca2+ from intracellular stores is delayed in onset by about 200 ms. By working at a lower temperature, 17 degrees C, we have now shown that the rise in cytosolic calcium concentratio...

O2-evolution activity and the Mn complex can be reconstituted in photosystem II by a process called photoactivation. We have studied the elementary steps in photoactivation by using electron paramagnetic resonance spectroscopy to probe electron transport in Mn-depleted photosystem II membranes. The electron donation reactions in Mn-depleted photosystem II were found to be identical with those i...

Plasma high-density lipoprotein is commonly estimated by measuring the cholesterol remaining in plasma supernatant solutions after other lipoproteins, which contain apolipoprotein B, are precipitated with heparin and Mn2+. The method (method I) now in use by the Lipid Research Clinics, in which Mn2+ is at 46 mmol/liter final concentration, is reasonably accurate, but precipitation and sedimenta...