Interfaces molecular surfaces

Persson, P., Axe, K. (2005). Adsorption of oxalate and malonate at the water-goethite interface molecular surface speciation from IR spectroscopy, Geochim. Cosmochim. Acta Vol. 69, No. 3, pp. 541-552, 0016-7037. 

Zhuang X, Miranda P B, Kim D and Shen Y R 1999 Mapping molecular orientation and conformation at interfaces by surface nonlinear optics Phys. Rev. B 59 12 632-40... 

The CoA binding tunnel provides access to the internal cavity. B. Molecular surface representation of the CHS-CoA complex oriented as shown in (A). In the -bottom panel, the two CHS monomers are separated and rotated slightly to highlight the flat dimerization interface along with the methionine side chain and dyad related hole in the backside of the CHS active site. 

Air-water flow regimes, 22 773 Air-water interface, molecular recognition at, 26 799-800 AISI 403 alloys, 23 511 AISI alloy steels, 23 299-300 Ajmalicine, 2 94, 95, 96, 100 Ajmaline, 2 94, 95, 96-97 AK-UFVE contactor, 20 768 A1203 surface scale, 23 507-508 Alabaster, 4 583... 

Molecular recognition, 16 768-811 24 31 at the air-water interface, 16 799-800 artificial receptors for substrate recognition, 16 792-794 charge attraction dominated, 16 779-781 chiral recognition, 16 789-791 hydrogen bond dominated, 16 781-782 at interfaces and surface monolayers, 16 796-801... 

The large and small subunits interact extensively with each other burying the catalytic site and the proximal [4Fe-4S] cluster at about 3nm from the molecular surface. It is quite remarkable that the active site and the two most buried [FeS] clusters are located close to the almost planar subunit interface. The large subunit is anchored to the small subunit by about twenty-five side chains, of which several very conserved ones interact with the proximal [4Fe-4S] cluster, pointing to the role of this cluster as a direct partner of the catalytic site. 

Contaminant volatilization from subsurface solid and aqueous phases may lead, on the one hand, to pollution of the atmosphere and, on the other hand, to contamination (by vapor transport) of the vadose zone and groundwater. Potential volatihty of a contaminant is related to its inherent vapor pressure, but actual vaporization rates depend on the environmental conditions and other factors that control behavior of chemicals at the solid-gas-water interface. For surface deposits, the actual rate of loss, or the pro-portionahty constant relating vapor pressure to volatilization rates, depends on external conditions (such as turbulence, surface roughness, and wind speed) that affect movement away from the evaporating surface. Close to the evaporating surface, there is relatively little movement of air and the vaporized substance is transported from the surface through the stagnant air layer only by molecular diffusion. The rate of contaminant volatilization from the subsurface is a function of the equilibrium distribution between the gas, water, and solid phases, as related to vapor pressure solubility and adsorption, as well as of the rate of contaminant movement to the soil surface. 

Atoms and molecules in strong electric and magnetic fields , Condensed matter clusters and crystals, surfaces and interfaces , Molecular electronics molecular materials ,... 

The structure of the lyotropically mesomorphous lattice is made up of multimolecular units called mesoaggregates. These are surrounded by an intervening liquid. Lyotropic mesomorphism is therefore closely related to the tendency of lipids to accumulate at interfaces. The surface activity is a consequence of the same dualistic polar/non-polar molecular structure that causes the formation of micelles in solutions of association colloids (I, 2, 3, 4, 5, 6). 

Stick models of the type shown in Plate 15a are the simplest and fastest type of model to compute and display because they represent the molecule with the smallest possible number of lines drawn on the screen. Stick models are relatively open, so the viewer can see through the outer regions of a complex molecule into the interior or into the interface between models of interacting molecules. But when the viewer wants to explore atomic contacts, a model of the molecular surface is indispensable. 

In molecular beam epitaxy (MBE) [317], molecular beams are used to deposit epitaxial layers onto the surface of a heated crystalline substrate (typically at 500-600° C). Epitaxial means that the crystal structure of the grown layer matches the crystal structure of the substrate. This is possible only if the two materials are the same (homoepitaxy) or if the crystalline structure of the two materials is very similar (heteroepitaxy). In MBE, a high purity of the substrates and the ion beams must be ensured. Effusion cells are used as beam sources and fast shutters allow one to quickly disrupt the deposition process and create layers with very sharply defined interfaces. Molecular beam epitaxy is of high technical importance in the production of III-V semiconductor compounds for sophisticated electronic and optoelectronic devices. Overviews are Refs. [318,319],... 

The first-order dependence of the deactivation constant was found to be proportional not only to the power imparted by the impeller but also to the area between the liquid and the glass wall, air surface, or poly(tetrafluoroethylene) (PTFE) surface (Colombie, 2001). Hydrophobic PTFE and air interfaces increased lysozyme inactivation fourfold over glass. In addition, the number and thus the molecular surface of inactivated enzymes, which are more hydrophobic than native enzymes, enhanced lysozyme inactivation and aggregation. 

Figure 1. (a) X-ray crystal structure of horse-heart ferricytochrome c.8 All protein atoms are shown in the C.-P.-K. form, while the heme group is shown in the stick form. All Arg and Lys residues are colored blue, while Glu and Asp are colored in red, to contrast the destribution of the most ionizable side chains, (b) The X-ray crystal structure of horse heart ferricytochrome c in complex with horse cytochrome c peroxidase (cep).9 The peroxidase is shown as a molecular surface model, with blue regions depicting positive and red representing negative electrostatic potential. Note the cluster of negative potential on ccp that surrounds the contact interface. 

Interfacing Cell Surface Receptors to Hybrid Nanopattemed Surfaces A Molecular Approach for Dissecting the Adhesion Machinery... 

Implicit in this model is the assumption that molecular diffusivity and Henry s Law constant are directly and inversely proportional, respectively, to the gas flux across the atmosphere-water interface. Molecular diffusion coefficients typically range from 1 x 10-5 to 4 x 10-5 cm2 s-1 and typically increase with temperature and decreasing molecular weight (table 5.3). Other factors such as thickness of the thin layer and wind also have important effects on gas flux. For example, wind creates shear that results in a decrease in the thickness of the thin layer. The sea surface microlayer has been shown to consist of films 50-100 pm in thickness (Libes, 1992). Other work has referred to this layer as the mass boundary layer (MBL) where a similar range of film thicknesses has been... 

Fig. 1. A. A cavity in the dielectric, containing a central water molecule and its neighbors. The radius of the cavity is considered large enough, for the molecular details of the dielectric outside the cavity to be ignored. Consequently, the dielectric outside die cavity can be considered as a homogeneous and continuous medium. B. A schematic structure of the silica-water interface. Each surface dipole exerts an average field on die water molecules above him the fields generated by the remote dipoles are neglected.

The study of LB films by ESCA and SIMS provides some important lessons for the metal polymer interface. The surface chemistry of polycrystalline silver is active enough to effect the protonation process to form molecular ions. Yet, the chemistry is not sufficient to completely deprotonate the fatty acids and produce carboxylate salts with the silver as counter ion. The... 

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