Oxidation continued zirconium

Black body radiators are used as sources of infrared radiation in the range 2-15 yum, e.g. the Nemst glower, which consists of a hollow rod made of the fused oxides of zirconium, yttrium and thorium. For use it is preheated and, when a voltage is applied, it emits intense continuous infrared radiation with very little visible radiation. 

Dialkylaminoethyl acryhc esters are readily prepared by transesterification of the corresponding dialkylaminoethanol (102,103). Catalysts include strong acids and tetraalkyl titanates for higher alkyl esters and titanates, sodium phenoxides, magnesium alkoxides, and dialkyitin oxides, as well as titanium and zirconium chelates, for the preparation of functional esters. Because of loss of catalyst activity during the reaction, incremental or continuous additions may be required to maintain an adequate reaction rate. 

Zirconium tetrafluoride [7783-64-4] is used in some fluoride-based glasses. These glasses are the first chemically and mechanically stable bulk glasses to have continuous high transparency from the near uv to the mid-k (0.3—6 -lm) (117—118). Zirconium oxide and tetrachloride have use as catalysts (119), and zirconium sulfate is used in preparing a nickel catalyst for the hydrogenation of vegetable oil. Zirconium 2-ethyIhexanoate [22464-99-9] is used with cobalt driers to replace lead compounds as driers in oil-based and alkyd paints (see Driers and metallic soaps). 

The possible employment of beryllium in nuclear engineering and in the aircraft industry has encouraged considerable investigation into its oxidation characteristics. In particular, behaviour in carbon dioxide up to temperatures of 1 000°C has been extensively studied and it has been shown that up to a temperature of 600°C the formation of beryllium oxide follows a parabolic law but with continued exposure break-away oxidation occurs in a similar fashion to that described for zirconium. The presence of moisture in the carbon dioxide enhances the break-away reaction . It has been suggested that film growth proceeds by cation diffusion and that oxidation takes place at the oxide/air interface. ... 

Continuous (barrier, passivation) films have a high resistivity (106Q cm or more), with a maximum thickness of 10 4cm. During their formation, the metal cation does not enter the solution, but rather oxidation occurs at the metal-film interface. Oxide films at tantalum, zirconium, aluminium and niobium are examples of these films. 

Precipitation of the coating from aqueous solutions onto the suspended Ti02 particles. Batch processes in stirred tanks are preferred various compounds are deposited one after the other under optimum conditions. There is a very extensive patent literature on this subject. Continuous precipitation is sometimes used in mixing lines or cascades of stirred tanks. Coatings of widely differing compounds are produced in a variety of sequences. The most common are oxides, oxide hydrates, silicates, and/or phosphates of titanium, zirconium, silicon, and aluminum. For special applications, boron, tin, zinc, cerium, manganese, antimony, or vanadium compounds can be used [2.40], [2.41],... 

In the same year Jones and Cunningham continued these experiments (2) and found that the cerium and the berkelium adsorption on zirconium phenylarsonate carrier were similar regardless of the oxidizing agent (bichromate, chlorate, hypochlorite, or bromate), or the medium (IN nitric acid, IM lithium perchlorate-perchloric acid at hydrogen ion... 

Russian workers have continued their studies on the production of alkyl-pyrrolizidines from furan derivatives by catalytic dehydration. The original catalyst used was thorium oxide on alumina, but improved yields were obtained with zirconium oxide on alumina [Eq. (5)]. In the formation of... 

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