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Antimony dispersion

An antimony containing intermetallic alloy compound consisting of molybdenum and antimony dispersed in an amorphous carbon matrix was developed using a high-energy mechanical milling technique (119). This material was used as the anode for a sodium-ion battery... [Pg.112]

Tin babbitts are based on the tin—antimony—copper system and commonly contain about 3—8% copper and 5—8% antimony. Within a soft, sohd-solution matrix of antimony in tin are dispersed small hard particles of the intermetaUic copper—tin, Cu Sn [12019-69-1] (13). [Pg.3]

Some heavy metals and semi-metals are quite toxic (chromium, lead, and antimony) and expensive care is needed to prevent them from being dispersed in the environment. Lead in gasoline and paint has been... [Pg.775]

Additions of antimony, bismuth and tin to the lead appear to be detrimental. There is an indication that the addition of 0 - l<7o Ag is almost as effective as 1% and additions as low as 0-01% has been utilised in practice. Dispersion-hardened lead alloys have been unsatisfactory, showing pronounced spalling in the direction of extrusion. Pb-0-lTe-0-lAg has been also used with apparent success" . [Pg.182]

A mixture of monolauryl phosphate sodium salt and triethylamine in H20 was treated with glycidol at 80°C for 8 h to give 98% lauryl 2,3-dihydro-xypropyl phosphate sodium salt [304]. Dyeing aids for polyester fibers exist of triethanolamine salts of ethoxylated phenol-styrene adduct phosphate esters [294], Fatty ethanolamide phosphate surfactant are obtained from the reaction of fatty alcohols and fatty ethanolamides with phosphorus pentoxide and neutralization of the product [295]. A double bond in the alkyl group of phosphoric acid esters alter the properties of the molecule. Diethylethanolamine salt of oleyl phosphate is effectively used as a dispersant for antimony oxide in a mixture of xylene-type solvent and water. The composition is useful as an additive for preventing functional deterioration of fluid catalytic cracking catalysts for heavy petroleum fractions. When it was allowed to stand at room temperature for 1 month it shows almost no precipitation [241]. [Pg.615]

Another way to obtain, under suitable conditions, stable dispersions of sur-factant-stabihzed nanoparticles consists in the direct suspension of some materials in w/o microemulsions. The formation of stable dispersions of rutile (size 80-450 mn) and carbon black (200-500 nm) in AOT// -xylene and of rutile, lead chloride, aluminium, antimony in solutions of calcium soaps in benzene has been reported [219,220],... [Pg.492]

The addition of finely dispersed solid particles improves the IR absorption of the polymer and positively influences blowing of the preforms. Such solid particles can be obtained by the reduction of Sb3+ to metallic antimony during polycondensation by the addition of trivalent phosphorous compounds such as phosphonic acid or its esters (phosphites). However, only a slight improvement in properties could be achieved by this approach [35],... [Pg.480]

Acidity, 27 284, 285 catalytic performance, 30 121 crystalline titanium silicates, 41 319-320 estimating, 37 166 heteropoly compounds, 41 139-150 ion exchange and, zeolites, 31 5-6 sulfate-supported metal oxides, 37 186-187 surface, monolayer dispersion, 37 34-35 tin-antimony oxide, 30 114-115, 125-1256 Acids, see also specific compounds adsorption of, on oxide surfaces, 25 243-245... [Pg.37]

Key indicators of alteration and proximity to ore are increased K2O (particularly in the shale component) near complete loss of Na20 increased FeO (particularly in the siltstone-sandstone component) and increased CO2 in shale. These changes reflect the development of iron carbonate (siderite and ankerite) by carbonate introduction and some alteration of existing calcic carbonate in siltstone-sandstone samples. Destruction of albite, absence of chlorite and increased abundance of muscovite due to potassic alteration, are the other major mineral alteration effects in the altered host rocks. Trace elements enriched in the primary dispersion zone are Zn, Pb, Ag, Sb, As, Rb, and TI. Antimony provides the most consistent and extensive trace element dispersion halo around the deposit and is also preserved in most of... [Pg.314]

CO2, most obvious in shale and depletion of Na. Many ore-related elements show primary dispersion (up to 300 m in the case of Zn), but their distribution is patchy or inconsistent. Antimony provides the most consistent primary dispersion pattern for the trace elements. [Pg.316]

The conditioning agents usually consist of a phosphate and a potassium salt, as well as zinc, antimony, and aluminum compounds. The purpose of these additions is to improve the final properties of the pigment, including color, photochemical stability, and dispersibility, as well as to catalyze the formation of rutile from die anatase hydrate. [Pg.1621]

Two hundred twenty four Chinese coins (Song Dynasty, ca. 990-1080 A.D.) were analyzed via energy dispersive X-ray fluorescence spectrometiy for the following elements copper (Cu), zinc (Zn), tin (Sn), lead (Pb), iron (Fe), nickel (NO. manganese (Mn), antimony (Sb), gold (Au), platinum (Pt), palladium (Pd), and silver (Ag). The coins routinely appear to be leaded bronze. However, the amount of lead present in these coins was in many cases significantly higher than expected. [Pg.231]

Thirty six small copper coins issued under the authority of Herod Agrippa I were analyzed using energy dispersive X-ray fluorescence spectrometry for copper, zinc, tin, lead, antimony, iron, gold, silver, and several other elements. This series of coins show significant amounts of lead in the coins, but an otherwise unadulterated bronze composition, with very little in the way of trace elements. The metallurgical make up of the samples and implications of the findings are presented here. [Pg.246]

The multifunctionality is achieved through either the combination of two different compounds (phase-cooperation) or the presence of different elements inside a single crystalline structure. In antimonates-based systems, cooperation between the metal antimonate (having a rutile crystalline structure), employed for propane oxidative dehydrogenation and propene activation, and the dispersed antimony oxide, active in allylic ammoxidation, is made more efficient through the dispersion of the latter compound over the former. In metal molybdates, one single crystalline structure contains both the element active in the oxidative dehydrogenation of the hydrocarbon (vanadium) and those active in the transformation of the olefin and in the allylic insertion of the N H2 species (tellurium and molybdenum). [Pg.298]

Ashley, P.M., Graham, B.P., Tighe, M.K. and Wolfenden, B.J. (2007) Antimony and arsenic dispersion in the Macleay River catchment, New South Wales a study of the environmental geochemical consequences. Australian Journal of Earth Sciences, 54(1), 83-103. [Pg.524]

At the higher metal level (2.0-4.5% Ni with up to 2% Sb) used to study artificially contaminated materials, XRD results have shown the formation of Ni-Sb alloys (NiSb x<0.08) whereas XPS data have indicated that a non-reducible antimony oxide, a well dispersed reducible Sb phase together with reducible Sb (that form an alloy with reducible Ni), were present. Selective chemisorption data for unsupported Ni-powders showed that one surface structure can effectively passivate 2-3 Ni atoms with respect to H2 chemisorption. XPS examination confirmed that Sb segregates at the surface of Ni particles where it can drastically affect the electron properties of neighboring Ni atoms thus reducing their activity. [Pg.354]

During the 1970-1980s, a mixture of ammonium fluoroborate and antimony oxide was offered on the market. This mixture was used in polypropylene with dechlorane (a chlorine source) to achieve V-0. In the absence of added halogen source, the mixture can also achieve V-0 and a LOI of 33% in PP at a loading of about 37.5%. It was claimed that the mixture can be easily dispersed, has excellent UV stability, and is non-blooming, nonvolatile, and odorless. However, its water absorption in high humidity areas was a deficiency of this additive. [Pg.229]

A further Raman investigation of the effect of the antimony-to-vanadium atomic ratio, gave evidence that the formation of VSbCh resulted in higher yields of acrylonitrile when surface vanadium oxide species were also present (Banares et al., 2002 Guerrero-Perez and Banares, 2004). The presence of surface alkoxy species was not observed in the absence of dispersed surface vanadium oxide species. [Pg.100]

Oliver [190] recommends the dissolution of the polymer if possible (see above) but in other cases a wet ashing procedure was used. The sample was heated with 2—3 ml of concentrated sulphuric acid and then hydrogen peroxide added drop-wise until the organic matter was destroyed. Twenty elements were determined in a 2% solution of polymer. Polymers may be dispersed in an organic solvent and trace metals removed by leaching with an appropriate aqueous solution, preferably the procedure should be repeated more than once to ensure complete extraction. To determine antimony in fire-retardant polypropylene, the sample was dispersed in xylene and extracted with 6M hydrochloric acid under reflux [191]. The filtered acid layer was combined with two further extracts prior to aspiration into the air/acetylene flame and measurement at 217.6 nm. Martinie and Schilt [45] reported that nylon would dissolve completely in perchloric/nitric acid digestion but potentially explosive problems were encountered in the dissolution of Amberlite resins and rubber. [Pg.430]


See other pages where Antimony dispersion is mentioned: [Pg.221]    [Pg.407]    [Pg.221]    [Pg.407]    [Pg.455]    [Pg.487]    [Pg.327]    [Pg.426]    [Pg.429]    [Pg.759]    [Pg.605]    [Pg.945]    [Pg.1819]    [Pg.253]    [Pg.139]    [Pg.202]    [Pg.327]    [Pg.560]    [Pg.719]    [Pg.717]    [Pg.1906]    [Pg.1819]    [Pg.439]    [Pg.316]    [Pg.146]    [Pg.99]    [Pg.7]    [Pg.159]    [Pg.391]    [Pg.139]    [Pg.392]   
See also in sourсe #XX -- [ Pg.30 ]




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