Secondary phases

The GdAlgB O QiCe ", Tb " is synthesized by a soHd-state firing of the rare-earth coprecipitated oxide plus boric acid and MgCO at 900° C in a slightly reducing atmosphere. As in the case of the lanthanum phosphate phosphor, a flux is usually used. The synthesis of this phosphor is further comphcated, however, by the fact that it is a ternary system and secondary phases such as gadolinium borate form and must then react to give the final phosphor. 

Table 3 Hsts the characteristics of CAC mineral constituents that can occur in CAC of varying purities. The primary hydraulic setting cement phase in all CAC grades is CA [12042-68-1/, CaO AI2O2 the main secondary phase in 70% AI2O2 CAC is Ca2, [12004-88-5] CaO 2AI2O2. CA2 and C 2 ...

The six secondary phases are obtained by shorting the centre points of each of the three-phase windings of a 3p transformer secondary. 

High ratios in groundwaters can be generated where U is concentrated in secondary phases and weathering is limited. For example, U can be precipitated when groundwaters become anoxic since reduced is much more insoluble. Therefore, concentrations are greatly lowered, and ratios increase due to efficient recoil from precipitated... 

Late latent Patients should be considered to have late latent syphilis if the aforementioned criteria (early latent) are not met. In both stages, patients are usually asymptomatic and the lesions noted in the primary and secondary phase usually resolve however, individuals are still seropositive for T. pallidum. 

In the case of the higher temperature crystallization, as will be shown in Sect. 4, the theory of Doi et al. is applicable without doubt since the primary phase separation involves the transition from the isotropic to nematic phase, but in the case of the glass crystallization near Tg described above its applicability is unclear since the observed data may correspond to the secondary phase separation. However, if the secondary phase separation occurs, the primary phase separation must have proceeded prior to that. In a rapidly quenched glass even if the primary phase separation had already taken place, it would be still incomplete, so that it will re-start by heating. 

Therefore, in the case of glass crystallization just above Tg we may possibly see a secondary phase separation of the spinodal decomposition (SD) type occurring inside the dense region caused by the first SD. 

Fig. 25 Annealing time evolution of the difference SAXS intensity in the induction period (a) and the crystallization period (b) for the melt crystallization of PET at 244 °C [18]. This system corresponds to crystallization from the metastable state where a nucle-ation and growth type of primary phase separation first occurs followed by the spinodal decomposition type secondary phase separation...

J. H. Westbrook, Temperature Dependence of the Hardness of Secondary Phases Common in Turbine Bucket Alloys, Trans. TMS-AIME, 209,898 (1957). 

Processing conditions were sought to prevent the formation of the secondary phase, to favor growth conditions of (112)-oriented films, and to avoid the... 

Variation of the deposition zone temperature affected the film stoichiometry and crystalline structure while not significantly affecting the deposition rate. A deposition zone temperature was optimized at 395 °C to produce (112)-oriented films without any detectable secondary phases. The susceptor location within the furnace did not affect the stoichiometry of deposited films, but it did alter morphology. Moving the susceptor toward the evaporation zone... 

Alvarez-Garcfa, J Perez-Rodrfgucz, A. Romano-Rodrfguez, A. Morante, J. R. Calvo-Barrio, L. Scheer, R. Klenk, R. 2001. Microstructure and secondary phases in coevaporated CuInS2 films Dependence on growth temperature and chemical composition. J. Vac. Sci. Technol. A 19 232-239. 

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