Interlamellar region

The balance between those molecules which are protonated and those which are not has emerged as an inportant function in determining the course of any reaction occurring within the Interlamellar region. One carefully studied reaction is that of the elimination of ammonia from amines (21), a reaction proceeding by two sinple steps... 

The catalytic application of clays is related closely to their swelling properties. Appropriate swelling enables the reactant to enter the interlamellar region. The ion exchange is usually performed in aquatic media because the swelling of clays in organic solvents, and thus the expansion of the interlayer space, is limited and it makes it difficult for a bulky metal complex to penetrate between the layers. Nonaqueous intercalation of montmorillonite with a water-sensitive multinuclear manganese complex was achieved, however, with the use of nitromethane as solvent.139 The complex cation is intercalated parallel to the sheets. 

The inductive effect of the carbon chain in the clay phase amounts to (only) 5 to 7 % of the effect in the gas phase. Ammonium cations in the interlamellar region of clay minerals are therefore less hydrated than in equilibrium solution. The free energy of alkylammonium exchange increases with charge density from Laponite (42) < Red Hill montmorillonite (40) < Camp Berteau montmorillonite (41) in line with the smaller interlamellar hydration status of the adsorbed cation at higher charge density. 

Scheme 27. Enantioselective ring opening of cyclic oxides G and H by TMSN3 catalyzed by chiral Cr(III) Schiff base complexes within the cavities of zeolites Y 53, EMT 54 and into the interlamellar region of K-10 montmorillonite 55.

Layered zirconium phosphate and zirconium phosphonates Size-quantized ZnSe, PbS, CdS, and CdSe grown in the interlamellar region of layered zirconium hosts... 

Montmorillonites (smectite clays) have structures resembling that of pyrophyllite but the structure is not electrically neutral. Exchangeable cations are located in interlamellar regions of the clay and, furthermore, the clay can be flocculated such that the plate-like crystals compact with parallel c-axes to give coherent layers. The smectites are then attractive materials with which to modify electrodes. 

The FRAP apparatus can also be used in a semi-quantitative manner to measure the surface concentration and subsequent competitive displacement of adsorbed labelled species, such as the fluorescent-labelled protein in the adsorbed layer of a/w or o/w thin films [10]. This can be achieved by focusing the low power 488 nm beam on the film and detection of the emitted fluorescence using the FRAP photon counting photomultiplier. The detected fluorescence signal is proportional to the amount of adsorbed protein at the interfaces of the thin film provided that the incident laser intensity is kept constant. Calculations have proved that the contributions from non-adsorbed protein molecules in the interlamellar region of the film are negligible [12],... 

The emission spectrum of Ru(bpy)21 in HZrP and HexA-ZrP had maxima at 620-625 nm. In both cases, quenching by ferricyanide was used to distinguish between the Ru(bpy)2+ adsorbed on the outer surface and in the interlamellar regions. For HexA-ZrP, the Stern-Volmer plot was nonlinear and this nonlinearity was interpreted as due to the adsorption of Ru(bpy) + at two different places. The Stem-Volmer constant (KSv) for the major component was estimated to be 7200 M 1 and this value is of the same order of magnitude as that of Ru(bpy)f1 -kaolin [85], in which Ru(bpy)21 is known to bind on the external surface, and both values are much smaller than that observed in aqueous solution (23,000 M1) [75b],... 

The double-striation morphology has tentatively been attributed to Pt nucleation on the fold edges of on-edge lamellae, similar to Au nucle-ation on the fold edges or interlamellar regions of, e.g., on-edge lamellae in drawn, annealed films of polyoxymethylene [37] and epitaxially crystallized samples of various other polymers [38]. AFM is currently being used to characterize further this feature. 

Starting from clays, it is possible to develop an additional group of materials with large pores, whose framework is composed of layered structures with pillars in the interlamellar region [122], These materials are the so-called pillared clays (PILCs). 

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