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Lattice reconstruction

The first electrochemical reduction of LCO was studied by chronoamperometry [283]. This method serves as an effective instrument for studying the phase composition and oxide properties [84], The cathodic current maximum was attributed [283] to the process of lattice reconstruction in the near-surface cuprate layers in the course of de-doping (the process similar to nucleation). Of prime interest for the development of LCO electrochemistry is the more efficient measurement of equilibrium charging curves. Experience of equilibrium measurements on perovskite... [Pg.86]

The goal of reconstruction methods is to build model pore structures that match experimental structure data (including surface chemistry data) for the real materials, at least in a quafitative way. For example, models can be constructed that match the experimental structure factor, S(q), or TEM data, by reverse Monte Carlo (RMC), off-lattice reconstruction, or other methods. [Pg.110]

The clusters we study are known from constant energy simulations [6,16,18,40] and experimental data [41] to undergo at least two temperature-driven orientational order-disorder transformations below the freezing point. The current study confirms the finding [16] that there are two successive transformations First, when the cluster is cooled below its range of solidification, it exhibits a discontinuous solid-solid transformation, involving partial molecular orientation and lattice reconstruction. A further cooling induces... [Pg.139]

Levitz, P. 1998. Off-lattice reconstruction of porous media critical evaluation, geometrical confinement and molecular transport. Adv, Colloid Interface Sci. 77 71-106. [Pg.141]

In order to obtain reproducible results, the working electrode must be pretreated as explained in the following text the electrode used herein was polished with 600 emery paper and alumina suspension (0.3-0.2 pm granularity), washed in distilled water, immersed in a previously deaerated solution, and cathodically polarized at —0.9 V for 5 min. The latter step is important to reduce the oxide layer formed during polishing however, polarization times longer than this period have to be avoided, otherwise hydride formation and metal lattice reconstruction turn up as a consequence of molecular hydrogen inclusion. [Pg.198]

The a P transformation in silicon nitride requires a lattice reconstruction. This type of process occurs usually only when the transforming material is in contact with a solvent. The greater solubility of the more unstable a form drives it into solution after which it precipitates as the less soluble, more stable P form. The predominantly a silicon nitride powder used to produce dense silicon nitride ceramics is observed to transform to the P modification during the sintering process at temperatures in excess of 140QOC when the original a phase is in contact with a M-Si-O-N (M = Mg, Y, etc) oxynitride liquid phase. [Pg.29]

Fig. 2 A Multi-cluster CCA-type lattice reconstruction of SI (each point represents a primary silica sphere) B. Single-Cluster DLA-type off-lattice reconstmction of SI stmcture (Sphere DLA) C. Center attraction ballistic deposition reconstmction of S4 D. Comparison of the autocorrelation functions of reconstracted SI (left) and S4 (right) silica gels (points), with the experimental ones (solid lines). Fig. 2 A Multi-cluster CCA-type lattice reconstruction of SI (each point represents a primary silica sphere) B. Single-Cluster DLA-type off-lattice reconstmction of SI stmcture (Sphere DLA) C. Center attraction ballistic deposition reconstmction of S4 D. Comparison of the autocorrelation functions of reconstracted SI (left) and S4 (right) silica gels (points), with the experimental ones (solid lines).
The water adsoiption / draoipticHi properties in a mesoporous silica glass are investigated by way of Grand Canonical Monte Carlo simulations. The SPC and PN-TrAZ potential are used to describe water-water and water-silica interactions. The numerical sample of mesoporous silica glass (pore size 3.6 nm) was obtained by off-lattice reconstruction, known to reproduce in a realistic way the geometrical complexity of high specific surface Vycor. [Pg.535]

Nave S, Jackson B (2007) Methane dissociation on Ni( 111) The role of lattice reconstruction. Phys Rev Lett 98 173003... [Pg.57]

There are a number of techniques that have been successfully applied to synthesize modified hydrotalcites (48). The most commonly method used is the co-precipitation of two metal salts in alkaline solution at a constant pH value of about 10. Another method uses the classical ion exchange process in which the guest anions are exchanged with the anions in the interlayer spaces of preformed layered double hydroxides to produce specific anion intercalated modified hydrotalcites. StiU another method is a lattice reconstruction after heating, i.e., calcination, which is based on the structural memory effect of these materials, due to which the original structure is reproduced after rehydration. [Pg.210]


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See also in sourсe #XX -- [ Pg.210 ]




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