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 Physics , 2012, DOI: 10.1103/PhysRevE.86.036316 Abstract: We use a stochastic approach to show how Taylor dispersion is affected by kinetic processes of adsorption and desorption onto surfaces. A general theory is developed, from which we derive explicitly the dispersion coefficients of canonical examples like Poiseuille flows in planar and cylindrical geometries, both in constant and sinusoidal velocity fields. These results open the way for the measurement of adsorption and desorption rate constants using stationary flows and molecular sorting using the stochastic resonance of the adsorption and desorption processes with the oscillatory velocity field.
 Asian Journal of Scientific Research , 2012, Abstract: Metal Organic Frameworks (MOF) are three dimensional organic-inorganic hybrid crystalline materials where a metal containing inorganic cluster is coordinated to a polydentate organic ligand. MOF-5 consists of Zn4O inorganic moiety, that acts as secondary building unit, coordinating to benzene 1,4-dicarboxylate, a bidentate ligand that acts as spacers, to form a three dimensional structure. We report the synthesis of MOF-5 using zinc nitrate and terephthalic acid as precursors dissolved in dimethyl formamide. The synthesized MOF-5 has been characterized using Fourier Transform Infrared Spectroscopy, X-ray diffractometry, Thermal analysis, Scanning Electron Microscopy and Transmission Electron Microscopy. Surface morphology reveals well-ordered structures with large number of pores in meso-scale. Adsorption capability towards vapours and gases has been studied using ethanol and CO2 as the model vapours using a chemi-resistive approach. Present results indicate that MOF-5 is a promising candidate for CO2 sequestration and gas storage.
 Physics , 1993, DOI: 10.1063/1.467037 Abstract: A reversible adsorption-desorption parking process in one dimension is studied. An exact solution for the equilibrium properties is obtained. The coverage near saturation depends logarithmically on the ratio between the adsorption rate, $\k_+$, and the desorption rate, $\k_-$, \hbox{$\req\cong 1-1/\log(k_+/k_-)$}, when $\k_+\gg\k_-$. A time dependent version of the reversible problem with immediate adsorption ($k_+=\infty$) is also considered. Both heuristic arguments and numerical simulations reveal a logarithmically slow approach to the completely covered state, \hbox{$1-\rho(t)\sim 1/\log(t)$}.
 Physics , 1999, DOI: 10.1063/1.480715 Abstract: Many experimental studies of protein deposition on solid surfaces involve alternating adsorption/desorption steps. In this paper, we investigate the effect of a desorption step (separating two adsorption steps) on the kinetics, the adsorbed-layer structure, and the saturation density. Our theoretical approach involves a density expansion of the pair distribution function and an application of an interpolation formula to estimate the saturation density as a function of the density at which the desorption process commences, $\rho_1$, and the density of the depleted configuration, $\rho_2$. The theory predicts an enhancement of the saturation density compared with that of a simple, uninterrupted RSA process and a maximum in the saturation density when $\rho_2={2/3}\rho_1$. The theoretical results are in qualitative and in semi-quantitative agreement with the results of numerical simulations.