Titanium oxide (TiO2) nanoparticles are added to sunscreens as they have broad absorbance across the whole UV spectrum. Although photostable, TiO2 nanoparticles can de-excite via surface states giving rise to reactive oxygen species (ROS) formation within the sunscreen formulation. An increased ROS load can degrade organic components within the sunscreen, such as UV absorbers or anti-oxidants, ...

Reactive Mn(IV) oxide minerals are ubiquitous in the environment and control the bioavailability and distribution of many toxic and essential elements and organic compounds. Their formation is thought to be dependent on microbial enzymes, because spontaneous Mn(II) to Mn(IV) oxidation is slow. Several species of marine Bacillus spores oxidize Mn(II) on their exosporium, the outermost layer of t...

a r t i c l e i n f o On the basis of triangular-shaped [Mn 3 O] secondary building units, a novel two-dimensional (2D) manganese (III) complex, [NaMn III 3 O(sao) 3 (btec) 0.5 (H 2 O) 3 ]·1.25H 2 O (1) (H 2 sao = salicylaldoxime, H 4 btec = benzene-1,2,4,5-tetracarboxylate acid), was synthesized and structurally characterized. The structure of 1 consists of 2D coordination polymer based on [Mn...

The mechanisms of initial oxide growth on the equiatomic CoCrFeMnNi high entropy alloy were studied in situ by X-ray photoelectron spectroscopy clean, oxide-free surfaces exposed stepwise to low-pressure gaseous oxygen. Cr(III), Mn(III), Fe(III), Co(II) but no Ni(II) oxides formed at 100 °C, and Mn(II) 200 °C. Data quantification revealed a transition mechanism from selective oxidation 3D kinet...

Chronic exposure to excessive manganese (Mn) is the cause of a neurodegenerative movement disorder, termed manganism, resulting from degeneration of neurons within the basal ganglia. Pathogenic mechanisms underlying this disorder are not fully understood but involve inflammatory activation of glial cells within the basal ganglia. It was postulated in the present studies that reactive astrocytes...

Mineral deposits related to thermal springs are generally of the carbonate or silicate precipitation types. Numerous thermal waters have been studied worldwide for their extensive deposits (Italy, Iceland, New Zealand, USA). The occurrence of other deposit types, such as oxides, associated with hydrothennal activity are few. However, the almost pure manganese oxide deposit in Japan was recently...

Samples with the composition Ce0.9Gd0.1MnxO2−δ with x = 0.01, 0.02, and 0.05 Mn-addition were prepared by mixed oxide route from Ce0.9Gd0.1O2−δ and MnO2 and sintered at 1300 ◦C. The electronic conductivity was measured using a modified Hebb-Wagner technique, the electrical conductivity was investigated by impedance spectroscopy, and oxygen permeation was measured for the sample with x = 0.05. A...

The role of the composition of surface-coating materials in controlling trace metal adsorption in aquatic environments was investigated using natural biofilms that developed on glass slides in three New York State lakes and a water-supply well. Adsorption isotherms were obtained for Pb binding to each of the biofilms in solutions with defined Pb speciation at 258C and pH 6.0, with Pb concentrat...

Synthesis of new efficient catalysts inspired by Nature is a key goal in the production of clean fuel. Different compounds based on manganese oxide have been investigated in order to find their water-oxidation activity. Herein, we introduce a novel engineered polypeptide containing tyrosine around nano-sized manganese-calcium oxide, which was shown to be a highly active catalyst toward water ox...