Three-step fusion technique

In order to synthesize zeolites from fly ash by its activation with NaOH, attempts have been made to identify a suitable fly ash out of its two disposal sites (viz., dry site at the electrostatic precipitator and wet site at the lagoons in the thermal power plants) for conventional (i.e., one step) hydrothermal activation technique [1-10]. Subsequently, the fly ash ascertained to exhibit improved zeolitization potential has been prefered to undergo novel hydrothermal treatment processes (viz., three step activation by hydrothermal technique and three step fusions) to activate the fly ash significantly for synthesis of fly ash zeolites with high cation exchange cqjadfy [11-15]. The details of both the types of alkali activations (viz., conventional with the two ashes and three step activations with the superior ash) are presented in the following. 

Chapter 6 Major Findings of the Three-Step Activation Technique This chapter deals with the inferences derived from the novel method three step activation of the hopper ash, which has been ascertained to be the superior ash over the lagoon ash, as described in Chapter-5, by following hydrothermal activation method. Furthermore, this chapter also showcases the outcome of the three-step activation of the fly ash by fusion method to synthesize high grade zeolite-X. 

While CT-based three-dimensional (3-D) treatment planning already represented a major step compared to the 2-D era, integration of MRI and PET and refinement of image fusion techniques resulted in further significant improvements. 

Based on the hndings presented in this chapter, it can be concluded that the three-step activation of the hopper ash with NaOH results in minor variation in pH and reduction in electrical conductivity of the supernatant. Such activation is also responsible for reduction in Si and A1 contents of the supernatant, obtained after recycled treatments. Hence, the ftnal grade of the fly ash zeohtes gets improved (with high CEC and specific surface area, enhanced specific gravity, nano-sized fine particles of zeohtes and micro-sized new pores). The three-step activation of the fly ash by adopting the fusion technique has also been found to be effective for zeolitization of the fly ash. However, the presence of impurities in the ash residues obtained from the fusion process makes them inferior as compared to those obtained from the hydrothermal treatment. 

For almost all types of steel there is a similar problem in the dissolution step. Three elements, Al, Si, and W, behave differently in the analysis of the total content and require special methods. These methods are simple extensions of the technique, which in the case of the determination of acid soluble Al or Si, can simply be omitted. When, during the dissolution, an oxide residue remains, which in general consists of Si02 or A1203, this must be brought into solution with a fusion, and added to the rest of the sample. If the W concentration is higher than 0.5%, the dissolving acid solution should also include phosphoric acid. Thus, it is possible to produce a universal method for the elements that are contained in steel and which influence its properties. 

The QCM has added valuable information about the mechanism of vesicle fusion on a surface. For instance, Kasemo and coworkers have unraveled the formation of planar lipid bilayers on Si02 and glassy surfaces by means of the QCM with dissipation (QCM-D) technique in conjunction with SPR, atomic force microscopy (AFM), and computer simulations [5-12]. They found that the process of bilayer formation occurs in three successive steps (1) in the first stage, vesicles attach to the surface via inter molecular interactions (2) at a critical surface coverage, the vesicles start to rupture, fuse on the surface, and thus form bilayer islands coexisting with vesicles and uncovered substrate (3) eventually, a coherent bilayer is formed covering the entire surface. 

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