Titanium dioxide modified

Photocatalysts, based on titanium dioxide, were used for the purification of contaminated soil polluted by oil [442], Commercially produced slurry of titanium dioxide was modified with barium, potassium, and calcium. The experiments were performed under natural conditions in summer months (July and August) applying direct solar-light irradiation. The most active photocatalyst for soil purification was titanium dioxide modified with calcium. 

Wodka, D., Bielanska, E., Socha R.P. et al. 2010. Photocatalytic activity of titanium dioxide modified by silver nanoparticles. App/. Mater. Interfaces 1 1945-1953. 

K Chiang, R Amal, T Tran. Photocatalytic degradation of cyanide using titanium dioxide modified with copper oxide. Advances in Environmental Research, 6(4) 471-485,2002. 

The alkaline solutions can remove water-soluble polymers in the spinning mix and inert products such as titanium dioxide. Basic treatments can also hydroly2e a certain amount of the polyester itself. For some silk-like appHcations or for producing fine denier fabrics, this basic treatment can produce a 10—30% weight loss of polyester (190,196). Certain polyesters such as anionically modified polyester can undergo more rapid weight loss than regular polyester (189). 

Alkaline-Earth Titanates. Some physical properties of representative alkaline-earth titanates ate Hsted in Table 15. The most important apphcations of these titanates are in the manufacture of electronic components (109). The most important member of the class is barium titanate, BaTi03, which owes its significance to its exceptionally high dielectric constant and its piezoelectric and ferroelectric properties. Further, because barium titanate easily forms solid solutions with strontium titanate, lead titanate, zirconium oxide, and tin oxide, the electrical properties can be modified within wide limits. Barium titanate may be made by, eg, cocalcination of barium carbonate and titanium dioxide at ca 1200°C. With the exception of Ba2Ti04, barium orthotitanate, titanates do not contain discrete TiO ions but ate mixed oxides. Ba2Ti04 has the P-K SO stmcture in which distorted tetrahedral TiO ions occur. 

The formulation of calcium chelate materials is based upon the formation of a low-solubiUty chelate between calcium hydroxide and a sahcylate. Dycal utilizes the reaction product of a polyhydric compound and sahcyhc acid. Other sahcyhc acid esters can be similarly used. Vehicles used to carry the calcium hydroxide, extenders, and fillers may include mineral oil, A/-ethyl- -toluenesulfonamide [80-39-7] and polymeric fluids. The filler additions may include titanium dioxide [13463-67-7] zinc oxide, sihca [7631-86-9], calcium sulfate, and barium sulfate [7727-43-7]. Zinc oxide and barium sulfate are useflil as x-ray opacifying agents to ensure a density greater than that of normal tooth stmcture. Resins, rosin, limed rosins, and modified rosins may serve as modifiers of the physical characteristics in both the unset and set states. 

Tacconi NR, Chenthamarakshan CR, Rajeshwar K, Tacconi El (2005) Selenium-modified titanium dioxide photochemical diode/electrolyte junctions Photocatalytic and electrochemical preparation, characterization, and model simulations. 1 Phys Chem B 109 11953-11960... 

Sakthivel, S. and Kisch, H. (2003) Daylight photocatalysis by carbon-modified titanium dioxide. Angewandte Chemie International Edition, 42 (40), 4908-4911. 

Y. Mishima, J. Motonaka, K. Maruyama, and S. Ikeda, Determination of hydrogen peroxide using a potassium hexacyanoferrate(III) modified titanium dioxide electrode. Anal. Chim. Acta 358, 291-296... 

At higher temperatures, zirconium dioxide and titanium dioxide supports gave much greater stability along with polymer-based supports [100,101] based on polystyrene-divinyl benzene (PS-DVB) such as PLRP-S noted in Table 9.5. PS-DVB supports have been reported to give a serious column bleed at 250°C [66]. Polybutadiene (PBD) modified zirconia columns have been used at temperatures up to 300°C and carbon-coated zirconia has been used at temperatures up to 370°C [66]. Applications have included the separation of steroids [73] and herbicides [102].The specific order of column bleed varied depending on the detection method as shown in Table 9.5. 

S. Sakthivel and H. Kisch, Daylight Photocatalysis by Carbon-Modified Titanium Dioxide, Angew. Chem. Int. Ed. 2003,42, 4908. 

It appeared attractive to extend the work on emulsification of liquid-liquid systems by BG copolymers to solid-liquid systems. As a first approach a model system was studied which comprises titanium dioxide dispersed in toluene with modified styrene-butadiene block copolymers as dispersants. These studies are reported here. 

Several anthraquinone dyes are used in dyeing thermoplastics such as polymethacrylate, (modified) polystyrene, and polycarbonate. The dyes also are used in combination with titanium dioxide or other materials to provide body colors for the thermoplastics. Initially compounds with relatively simple structures were used, many of them drawn from stocks of existing intermediates. Since then new products designed to satisfy the specific requirements have become available. 

Lactose monohydrate, corn starch, modified starch, povidone 25000, magnesium stearate, HPMC, Macrogol 6000, talc, titanium dioxide, ferric oxide pigment, yellow NF... 

Hydrolysis in aqueous solution precipitates hydrated titanium dioxide which, after washing and drying, can be calcined at 800°C to remove water and residual Cl. This method has been the basis of producing titanium dioxide of 99.999% purity. If retaining a high specific surface area is important, it may be convenient to reduce the residual Cl content by Sohxlet extraction rather than calcination. For many electroceramic uses, the millability of the product is as important as the absolute purity. A number of process variants designed to modify particulate morphology have been described (67). 

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