Barium, manganese oxides

Barium Oxides hydroxides with Group 3 11 dements (Mn) Barium manganese oxide... 

Barium Oxides hydroxides Barium manganese oxide... 

Conditioning of the manganese oxide suspension with each cation was conducted in a thermostatted cell (25° 0.05°C.) described previously (13). Analyses of residual lithium, potassium, sodium, calcium, and barium were obtained by standard flame photometry techniques on a Beckman DU-2 spectrophotometer with flame attachment. Analyses of copper, nickel, and cobalt were conducted on a Sargent Model XR recording polarograph. Samples for analysis were removed upon equilibration of the system, the solid centrifuged off and analytical concentrations determined from calibration curves. In contrast to Morgan and Stumm (10) who report fairly rapid equilibration, final attainment of equilibrium at constant pH, for example, upon addition of metal ions was often very slow, in some cases of the order of several hours. 

Yellow ochres are earths composed essentially of clay coloured by hydrated ferric oxide they may contain siliceous sand, calcium carbonate, small proportions of manganese oxides, and sometimes basic ferric sulphate and calcium and barium sulphates. Chalk, gypsum and heavy spar may be added fraudulently and the colour may be " improved by artificial organic dyes, vegetable colours or chrome yellow. 

Metals passivation in the resid FCC unit may also be accomplished through the addition of metal traps. Tin, barium titanate, strontium titanate, magnesium oxide, manganese oxide, and specialized zeolite types and contents have all been used for vanadium trapping. In addition, zeolites coated with alumina and catalyst particles coated with rare earth have also been applied to resist vanadium poisoning. Antimony, bismuth, and specialized active high crystalline aluminas have all been used successfully to counteract the negative effect of nickel in the FCC unit. 

G. Scheele was the third chemist who tried to separate a new element from this mineral. In 1774 he submitted his paper On Manganese and Its Properties to the Stockholm Academy of Sciences in it he summed up the three years of studies of pyrolusite. In this extremely informative paper he reported the discovery of two metals (barium and manganese) and described two gaseous elements (later identified as chlorine and oxygen). Scheele established that manganese oxide differed from all earths known at the time. 

The second class of sol-gels contains redox-active metal oxides, such as tungsten oxide, vanadium pentoxide, manganese oxide, and other transition metal oxides. Moreover, many n-type semiconductors such as zinc oxide, barium titanate, and titanium dioxide can be used in this class (113). The structures of these gels are sensitive to the pH and oxidation state of the precursors. Many redox-active sol-gels exhibit electrochromism (different oxidation states exhibit different colors, allowing spectroscopic determination of redox states). These gels can also accommodate the reductive insertion of lithium and other moieties. 

Carbonates Barium carbonate (BaC03) and witherite (BaC03). Tertiary oxides with Group 3-11 elements (Mn) Bariinn manganese oxide. 

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