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The tracer exchange of molecules between the phase adsorbed in one-dimensional channels and the surrounding gas phase by molecular dynamics simulations is studied. It is seen that equilibrium concentration is reached faster at the boundaries and slower in the middle part of the channel in the case of single-file diffusion, which can be explained by the mechanisms of the normal diffusion laws and that which admits additional displacements causing an accelerated particle exchange.

Research was conducted to examine the visible light-induced reaction between 2,3-dimethyl-2-butene and O2 in zeolite NaY at -100 degrees C using rapid scan time-resolved FT-infrared spectroscopy. The growth of the sole product, 2,3-dimethyl-3-hydroperoxy-1-butene during a 150 ms photolysis pulse was observed. Results confirm that the sole physical property of the zeolite cage is responsible for the visible light-induced olefin oxidation.

Incrystalline concentration profiles of water, adsorbed in large crystals of CrAPO-5 and SAPO-5 under equilibrium with water vapor at one and 20 mbar, are determined with the use of inference microscopy. The results indicate high inhomogeneous distribution of incrystalline water in both crystal types at lower pressure.

The report stated that the equilibrium intracrystalline concentration profile of methanol was recorded in CrAPO-5 crystals by interference and FTIR microscopy. The study stated that two-dimensional concentration profiles of an unprecedented quality were reported, which showed a nonhomogeneous distribution of adsorbate in zeotite cyrstal under equilibrium with the adsorbate vapor.

The diffusion of poly(diallyldimethylammonium chloride) (PDADMAC) polycations in coacervates formed from PDADMAC and the protein bovine serum albumin (BSA) is studied. Several ensembles of PDADMAC polycations with different diffusivities are observed.

The article provides evidence of the suitability of the tracer zero-length column method in observing molecular transport under conditions of anomalous, single-file diffusion. The center-of-gravity diffusion mechanism is observed in single-file systems of finite length.

The evolution of internal concentration profile of methanol in two-dimensional (2-D) pore structure of ferrierite crystal is measured with the help of interference microscopy technique. The results have indicated the importance of measuring the evolution of concentration profiles, as this is crucial in determining the direction of internal transport, the presence of internal structural defects and surface/internal transport barriers.

The pulsed field gradient NMR diffusion measurements and molecular dynamics simulations show that the typical values of sticking coefficient are close to one. The infrared (IR) uptake measurements indicate that the values of sticking coefficient have high orders of magnitude.

The intracrystalline diffusion of methane and n-butane molecules in MFI-type zeolites at several temperatures and over a wide range of diffusion times is investigated applying the PFG NMR technique. The results of the study reveals that diffusion coefficients progressively decreasing with increasing root-meansquare displacements.

A study was conducted to examine zeolite-based acetyl radicals using time-resolved Fourier transform infrared spectroscopy. Solvent-free wafers were irradiated for 30 min at room temperature with 308 nm pulsed laser light. Results indicated good agreement between the concentration of acetyl radical and final products. Findings also showed that the transient determined in zeolite NaY after 1-naphthyl acetate was an acetyl radical interacting with Na+ ion.