Aluminum oxides surface

Lee, I. and Wool, R.P., Controlling amine receptor group density on aluminum oxide surfaces by mixed silane self-assembly. J. Thin Solid Films, 379, 94 (2000). 

In general, the stability of titanium oxide surfaces in moist environments is less of a concern than it is for aluminum oxide surfaces. For example, an FPL or PAA oxide on aluminum would be completely converted to hydroxide in less than 5 min after exposure to boiling water, whereas even after 24 h only slight changes such as crystallite formation and reduction in density of the cell structure occur for... 

Schlautman, M.A., Morgan, JJ. (1993b) Binding of a fluorescent hydrophobic organic probe by dissolved humic substances and organically-coated aluminum oxide surfaces. Environ. Sci. Technol. 27, 2523-2532. 

The ligand is hydroxyquinoline-sulfonate (HQS) which forms fluorescent AI-HQS complexes in solution. HQS forms surface complexes with the Al-centers of aluminum oxide surface these surface complexes are also fluorescent. Fluorescence as a function of time during HQS-promoted dissolution of aluminum oxide. Surface-associated fluorescence was calculated from the difference between measured total and dissolved fluorescence. 

Primer Epoxy vs. Nitrile-Modified Epoxy. The compatibility of the epoxy-polyamide primer with the nitrile-modified epoxy adhesive facsimile and the aluminum oxide surface was also evaluated by the wedge test, since earlier tests using the primer as the adhesive had failed immediately. As shown in Fig. 8, the addition of the primer directly to the prepared... 

The catalytic activity of aluminas are mostly related to the Lewis acidity of a small number of low coordination surface aluminum ions, as well as to the high ionicity of the surface Al-O bond [67,92]. The number of such very strong Lewis sites present on aluminum oxide surfaces depends on the dehydroxylation degree and on the particular phase and preparation. Depending on the activation temperature, the density of the strongest Lewis acid sites tends to decrease as the calcination temperature of the alumina increases (i.e., upon the sequence y — 5 —> 9, which is also a sequence of decreasing surface area and increasing catalyst stability). 

This work discusses the structure of films formed by a multicomponent silane primer as applied to an aluminum oxide surface as well as the interactions of this primer with the adhesive and oxide to form an interphase region with a distinct composition and properties. The mecanical properties and durability of adhesive joints prepared using this primer system have yet to be evaluated. 

The N(ls) spectra of these films show that the amines present in the regions of the film close to the aluminum oxide surface were protonated, an effect similar to that seen in the N(ls) spectra of the adhesive near the fracture surface of unprimed adhesive joints [15]. Figure 5 shows the spectra obtained from two... 

Organic primers formulated with corrosion inhibitors are typically applied to pretreated metal surfaces to protect the surfaces prior to adhesive bonding and during environmental exposure. Pike [7-11] found that inorganic primers, such as sec-butyl aluminum alkoxide, improved the durability of aluminum-epoxy bonds when applied to both porous and nonporous aluminum oxide surfaces. It was shown that the effective thickness of the inorganic primer was directly related to the degree of oxide porosity and the depth of the porous oxide layer resulting from the normally used pretreatments for aluminum [10,11]. 

Schultess, C. P., and C. P. Huang. 1991. Humic and fulvic acid adsorption by silicon and aluminum oxide surfaces on clay minerals. Soil Science Society of America Journal 5 5 34—42. 

We begin by defining two important terms absorption and adsorption. The International Union of Pure and Applied Chemistry offers precise definitions for absorption and adsorption (IUPAC, 1972). Absorption is used to describe a process where a component is transferred from one phase to another. Hydrogen gas can be absorbed by LaNis (Jurczyk, 2003). Adsorption is used to describe the increased or decreased concentration of a component at an interface. Water molecules will adsorb to an aluminum oxide surface (Al-Abadleh and Grassian, 2003). The concentration of water molecules on the aluminum oxide surface will be greater than the vapor phase, shown schematically in Figure 3.3. 

Templeton MK, Weinberg WH (1985) Adsorption and decomposition of dimethyl methylphos-phonate on an aluminum oxide surface, J Am Chem Soc 107 97-108... 

The aluminum oxide surfaces exhibit only a weak Bronsted acidity. Therefore, studies of its surface hydroxyls have usually dealt with their structure. IR spectroscopy appears the most informative and appropriate method for these purposes. The IR spectra cover a wide variety of hydroxyl stretching vibrations, and their assignment is frequently quite a problem. Primarily, it was based on electrostatic concepts and on the electrostatic theory of valency (138). 

Hachiya, K., M. Ashida, M. Sasaki, H. Kan, T. Inoue, and T. Yasunaga. 1979. Study of the kinetics of adsorption-desorption of lead(2+) ion on a gamma-aluminum oxide surface by means of relaxation techniques. J. Phys. Chem. 83 1866-1871. Heller-Kallai, L., and C. Mosser. 1995. Migration of Cu ions in Cu montmorillonite heated with and without alkali halides. Clays Clay Miner. 43 738-743. 

Half-Metallocene Group-4 Metal Precursors on Aluminum Oxide Surfaces... 

Partitioning and mobility of metal ions, metal complexes, and ligands in soils or sediments are affected by their adsorption onto a variety of substrates. As mentioned earlier (see Section 6.3.1), natural oxides offer suitable adsorption sites for some of these species and may even undergo dissolution as a result. Here, an understanding of the bonding phenomena is crucial. For example, the adsorption of [Co(III)EDTA] (here written as [ML]-) on hydrated aluminum oxide surfaces (written as =A10H) can be represented as ... 

Why are the electron energies of Okll and Ckll in Figure 7.3 different from those in Figure 7.2 Estimate the work function of an aluminum oxide surface from Figures 7.2 and 7.3. 

Smith, D.S. and Ferris, EG., Proton binding by hydrous ferric oxide and aluminum oxide surfaces interpreted using fully optimized continuous pK spectra. Environ. Sci. Technol., 35, 4637, 2001. 

Qi, R, Influence of aluminum oxides surface properties on catalyzed ozonation of 2,4,6-trichloroanisole, Separ. Purif. Technol., 2009. 

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