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Single-phase products

The preparation of single-phase products is difficult. For the Mo-B system, only Mo is deposited < 1060°C. At 1060-1260°C the deposit composition changes from Mo + M02B through MojB to MojB + MoB. Pure MoB is deposited at 1260-1450°C. Mixtures of MoB and MojB, are obtained above these T. For W metal, deposition proceeds at < 1150°C, after which W + WjB, pure W2B and WiB -f WB are successively deposited with increasing temperature < 1300°C. Pure phases of WB and W2B5 are obtained at 1400 and 1600°C, respectively. [Pg.278]

Ffgure 2.1 The distillation stage concept, to) General presentation of an ideal distillation stage (b) and (e) single-phase product (these are not ideal distillation stages) (tf) and phase product (these are ideal distillation stages). [Pg.21]

Cherivin et al. developed a non-alkoxide sol-gel method for the preparation of homogeneous nanocrystalline powders of Lo.85Sro.i5Mn03 (Cherivin et al., 2006). Calcination of the dried gels resulted in the crystallization of single-phase products at 700 °C with discrete particles free of hard agglomeration (Figure 57). [Pg.397]

Electrolysis is carried out at 1000 to BOOK of a mixture of alkali halide, metal oxide, and a borate. This is a process of industrial interest. However, high-purity and single-phase products are not easily obtained. [Pg.407]

Addition of a small amount of water (up to 5% by volume) usually facilitates the reaction, but larger amounts of water may disturb the formation of single-phase product by the formation of stable intermediates. [Pg.317]

A specific advantage of this method is the possibility for the variation of the metals and the fact that preparative amounts of the products are accessible as coarse crystalline and single phase products in short reaction times. The reactions may be interpreted as the dissolution of an electropositive metal in a nitrido analogous, polymeric acid (Si(NH)2) by the evolution of hydrogen. [Pg.694]

The ni3(P04)4 and U3(P04)4 phosphates were first characterized in 1957-1963 [15-18] as isostructural compounds with monoclinic unit cells, space group P2, or Pm, or P2 m. More recently, the data were critically revised in a number of papers [8,19-24], where the authors used new methods of studying solids, and carried out detailed experiments on the phase formation in the systems Th02 -P2O5 and UO2 - P2O5. In the authors opinion [8,19-24], attempts to synthesize single phase products such as "M3(P04)4" for both thorium and uranium [15-18] failed. This was also the case for the compounds of similar stoichiometry with neptunium (IV) and plutonimn (IV) [19, 24],... [Pg.317]

We have chosen as a simple model system the situation for which R H and R >phenyl. They both separately react very fast, and form single phase products easy to identify both by infrared spectroscopy ( i p.g at 2470 cm-l phenyl C-H fingerprint in the 700-800 cm l region) and by their very different layer repeat... [Pg.231]

Stoichiometric samples of CogSg can best be prepared by heating cobalt sulfate in a stream of H2/H2S at 525°C. Whereas it takes almost two weeks to obtain CogSg by the direct combination of the elements, pure single-phase products can be obtained from the sulfate in six hours. [Pg.250]

Historically, the research done on the Ca-Mn-0 system has been performed at high (>1000°) temperatures.1-9 The traditional ceramic synthesis approach to these complex oxides involves repeated high-temperature firing of the component oxides with frequent regrindings. These severe reaction conditions are necessary to obtain a single-phase product because of the diffusional limitations of solid state reactions. Such high-temperature syntheses naturally lead to crystalline, low-surface-area materials and often preclude the preparation of mixed metal oxides that are stable only at relatively low temperatures. [Pg.73]

Condenser and Pressure Control—Single-Phase Product... [Pg.526]

If the equipment utilizes only two wires for input (line and neutral), as a double insulated product, and there is no ground connection, it is then necessary to mark the product with the Class II symbol. Examples of rating labels for single phase products are ... [Pg.100]

Sparge of an inert gas, which continuously removed the highly volatile components, effectively producing a single phase product, which was 100% mesophase, with over 90% having a molecular weight less than 1500. [Pg.163]

A specially developed radiofrequency furnace, used for the inductive heating of the crucibles containing the reaction mixture, is advantageous for obtaining high yields and purities in these reactions [56]. Preparative amounts of nitridosilicates as coarsely crystalline single-phase products are accessible by this procedure in short reaction times. [Pg.535]

Solution combustion synthesis makes use of salts, such as nitrates, metal sulfates and carbonates, as oxidants and, reducing reagents, fuels such as glycine, sucrose, urea, or other water soluble carbohydrates. Nitrate acts as an oxidizer for the fuel during the combustion reaction. The powder can be a pyrolysed product of a single phase, but usually it is a combination of metal oxides and in some cases it needs subsequent heat treatment to form single-phase products, which are usually the results required in this process. [Pg.12]

The priderite structure is related to the hoUandite stracture and can give a single-phase product over a considerable range of stoichiometries near BaNiTiyOj. These Sb-free pigments were initially sold as heavy metal free pigments. [Pg.60]


See other pages where Single-phase products is mentioned: [Pg.421]    [Pg.422]    [Pg.455]    [Pg.684]    [Pg.155]    [Pg.105]    [Pg.14]    [Pg.155]    [Pg.234]    [Pg.234]    [Pg.711]    [Pg.247]    [Pg.250]    [Pg.226]    [Pg.298]    [Pg.245]    [Pg.443]    [Pg.230]    [Pg.254]    [Pg.211]    [Pg.585]    [Pg.57]    [Pg.11]    [Pg.228]    [Pg.143]    [Pg.14]    [Pg.418]    [Pg.267]    [Pg.175]   


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Condenser and Pressure Control—Single-Phase Product

Production phase

Productive phase

Single-phase

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