Batch adsorption from aqueous solutions in a slightly basic medium of Methylene Blue, up to 2500 mg/L, onto synthetic magnesium silicate (Florisil) of three particle size ranges (mean diameters of 112, 200 and 425 microm) was compared to the corresponding adsorption onto activated carbon and Amberlite XAD-2. The best fit of the kinetic results was achieved by a pseudo second-order equation. The...

As part of a theoretical study of adsorption processes in the chemical vapour deposition of silicon, thermochemical data are derived for the adsorption of Si—H species on the Si(111) and the dimer-reconstructed Si(001)-(2 xl) surfaces. Essential contributions to the heats of adsorption appear to be electron pairing and twoand three-body interactions. It is shown that when the bond energies are ...

Calcium ion induced aggregation and precipitation equilibria of b-casein were studied in the presence or absence of monoand polyphosphates at pH 5.5 and 7.5. We analyze the data by assuming ion binding at a well-defined stoichiometric ratio, leading to protein charge neutralization and formation of slightly soluble complexes. The precipitation curves are in good agreement with the model, showin...

This paper deals with a ratio-dependent functional response predator-prey model with a fractional order derivative. The ratio-dependent models are very interesting, since they expose neither the paradox of enrichment nor the biological control paradox. We study the local stability of equilibria of the original system and its discretized counterpart. We show that the discretized system, which is...

Abstract The nanostructured cyclically refreshable liquid amalgam film silver-based electrode (R-AgLAFE) was applied to study of the Bi(III) process in presence 2-thiocytosine and selected ionic surfactants. application voltammetrictechniques (SWV, CV, DC), as well electrochemical impedance spectroscopy (EIS) allowed determination kinetic which turn, defined catalytic effect also their correlat...

A published model for estimating service lives of organic vapor (OV) air-purifying respirator cartridges has been extended to include multiple organic vapors at all humidities. Equilibria among the OVs are calculated using Ideal Adsorbed Solution Theory, whereas the effects of adsorbed water are considered as due to micropore volume exclusion. Solubilities of OVs in water must also be taken int...

In this paper transport through nanochannels is assessed, both of liquids and of dissolved molecules or ions. First, we review principles of transport at the nanoscale, which will involve the identification of important length scales where transitions in behavior occur. We also present several important consequences that a high surface-to-volume ratio has for transport. We review liquid slip, c...

We study liquid adsorption in narrow rectangular capped capillaries formed by capping two parallel planar walls (a slit pore) with a third wall orthogonal to the two planar walls. The most important transition in confined fluids is arguably condensation, where the pore becomes filled with the liquid phase which is metastable in the bulk. Depending on the temperature T, the condensation in cappe...

We present a method to determine the local surface charge of solid-liquid interfaces from Atomic Force Microscopy (AFM) measurements that takes into account shifts of the adsorption/desorption equilibria of protons and ions as the cantilever tip approaches the sample. We recorded AFM force distance curves in dynamic mode with sharp tips on heterogeneous silica surfaces partially covered by gibb...

Three samples of hydrous chromium(III) oxide have been prepared by different procedures, and their electrokinetic mobilities have been measured. In mineral media, isoelectric points were found to be 8.45 0.15. This value is shifted from the solution isoelectric point by –0.35 0.15, due to the contribution of solvation energy to the energy of ionic adsorption. On the basis of a simple model, it ...