hydrous manganese dioxide nanoclusters are prepared by the oxidation of manganese (ii) ions with ammonium persulfate and used as a new sorbent for ag+ ion removal from aqueous medium. the synthesized compound is characterized using scanning electron microscopy, dynamic light scattering, energy dispersive analysis of x-rays, x-ray diffraction and bet surface measurements. scanning electron micro...

A&met-Non-stoichiometric manganese dioxide prepared electrochemically at room temperature and suspended in dilute sulphuric acid is used to oxidise isosafrole to piperonal in 54% isolated yield. The manganese dioxide-manganese@) sulphate system can be recycled electrochemically at high current density. It has the further advantage that water-soluble materials derived from the chemical oxidation...

Several Mousterian sites in France have yielded large numbers of small black blocs. The usual interpretation is that these 'manganese oxides' were collected for their colouring properties and used in body decoration, potentially for symbolic expression. Neanderthals habitually used fire and if they needed black material for decoration, soot and charcoal were readily available, whereas obtaining...

objective: this study investigated tissue damages induced by chronic subcutaneous administration of nano- and microparticles of manganese dioxide (mno2) on the liver, kidneys and testes of rats. methods: rats (n=210) were divided into three groups: control, mno2 nanoparticle injected and mno2 microparticle injected. the experimental groups received subcutaneous injections with either nano- or m...

A high yielding manganese dioxide mediated oxidation of benzylamines to the corresponding amides has been developed under mild reaction conditions. The mechanism for the conversion has been explored by (1)H NMR spectroscopy and the role of both manganese dioxide and molecular sieves in the reaction elucidated.

1. Suspensions of manganese dioxide given intravenously to the cat are virtually eliminated from the body in 1 week (168 hours). 2. As this process of removal goes on, there is a transfer of manganese from lungs to liver. 3. Similar suspensions of manganese dioxide given intravenously to rabbits are excreted more rapidly, owing to the fact that in these animals the lungs are not involved and th...

Laboratory and full-scale experiments were conducted for enhancing the coagulation of stabilised surface waters with high organic content by permanganate preoxidation. It was indicated that permanganate preoxidation enhanced both the processes of coagulation and filtration of selected surface waters, River Songhua water, Qitaihe Reservoir water and Ba Reservoir water. Permanganate preoxidation ...

Manganese dioxide nanofibers with length ranged from 0.1 to 1 μm and a diameter of about 4-6 nm were prepared by a chemical precipitation method. Composite electrodes for electrochemical supercapacitors were fabricated by impregnation of the manganese dioxide nanofibers and multiwalled carbon nanotubes (MWCNT) into porous Ni plaque current collectors. Obtained composite electrodes, containing 8...

The effect of UV (ultraviolet) irradiation on the adsorption of Au(III) ions on manganese dioxide and their reduction to Au(0) (gold with 0 valence state) was investigated using XPS (X-ray photoelectron spectroscopy) and 197Au Mössbauer spectroscopy. The UV irradiation accelerated the adsorption and the reduction. From the fact that the proportion of Au(0) estimated from Au 4f XPS spectra for s...