Surface for adsorption

Caputo A, Spamacci K, Ensoli B et al (2008) Functional polymeric nano/microparticles for surface adsorption and delivery of protein and DNA vaccines. Curr Drug Deliv 5 230-242... 

Allowance must be made for surface adsorption, which will also explain the deactivation and morphological changes on the electrode surface ... 

EXTRACT and O-METHYLATED EXTRACT. The sorption of benzene by the extract and the O-methylated extract is characterized by a rapid, initial uptake followed by a very slow approach to equilibrium. Such sorption behavior is very similar to that of glassy polymers. Thus we have chosen to interpret the sorption curves shown in Figures 2 and 3 in terms of the Berens-Hopfenberg model developed for the sorption of organic vapors into glassy polymers.(lS) By doing so, we attempt to correct the total sorption values for surface adsorption in order to calculate x parameters. 

Humidity has a significant influence on the photocatalytic oxidation of aromatic contaminants in the gas phase. This is of particular interest, because commercial photocatalytic systems will be required to operate under a broad range of relative-humidity levels. The specific influence of relative humidity on the photocatalytic reaction has generally proved rather difficult to quantify because water has a dual role It may compete with contaminants for surface adsorption sites (a negative influence) and it plays a role in the regeneration of surface hydroxyl groups during photocatalysis (a positive influence). 

The same analyses of the data on FeCp-Et and FeCp-H give a 1, and kal has been shown to be much smaller than that of FeCp-PrOH. For a = 1 and small kalCw/rx, Q(t) in Eq. 13 is reduced to Eqs. 7 and 8 (diffusion-limited equation). The success in analyzing the data in Figure 19 by Eq. 13 demonstrates an important role of surface adsorption of FeCp-PrOH in the fast MT processes. On the other hand, the Q(t) data on FeCp-EtOH have been analyzed by Eq. 13, similar to those of FeCp-PrOH. These results indicate that the hydroxyl group of FeCp-PrOH or FeCp-EtOH possessing small Keq is a very favorable substituent for surface adsorption. 

These stable DIP concentrations are believed to be controlled by a buffering of DIP through the adsorption and desorption onto metal oxide surfaces. This P buffering is believed to balance the low availability of SRP in higher-salinity waters, which occurs from phytoplankton uptake and anionic competition for surface adsorption sites. 

Information from beam exposures of the sample can be obtained a number of ways. For surface adsorption probabilities greater than 0.03, the King and Wells method [16] can accurately be employed to determine initial adsorption probabilities of a gas species. In short, a King and Wells measurement monitors the partial pressure of the scattering chamber before, during, and after exposure of the sample to the beam flux. A typical reflectivity measurement can be seen in Fig. 2. 

Figure 6.41. Illustration of the chemisorption of a nanostructure onto a hydroxylated Ti02 surface. The hydroxyl groups on the periphery of the nanostructure stabilizing agent provide the handle for surface adsorption. Reproduced with permission from Liu, S. Zhu, T. Hu, R. Liu, Z. Phys. Chem. Chem. Phys. 2002,4, 6059. Copyright 2002 PCCP Owners Societies.

In addition to the electrochemical techniques, many insitu and exsitu surface analytical techniques are used in studies of silicon electrodes, such as ellipsometry for determining thin surface film thickness, ° infrared spectroscopy for surface adsorption, 260,424 surface composition, and for... 

The fundamental parameter measured In gas chromatography Is the retention volume, which Is the volume of carrier gas required to elute a zone of solute vapour. For surface adsorption,... 

II would be flius possible lo evaluate parameters Co and Ci for surface adsorption and Ihe interaction parameter B of the excess Gibbs energy of mixing in the bulk liquid from the polynomial coefficients of the concentration dependency of the surface tension. It should be noted that there are three unknown variables and four equations. Hence also the third-order polynomial would be adequate to calculate the parameters. 

This completes the modifications of the general chemical equilibrium method for surface adsorption involving a constant-capacitance model. The equations are summarized in Table III. 

Here is the moles of water adsorbed per gram solid for the formation of a monolayer, AH, is the enthalpy change for surface adsorption of water vapour, AHl is the enthalpy change for water condensation, x is the partial pressure of vapour, p/p°, and q is the measured enthalpy change for the sorption of x. 

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