Modified nanoparticles

Finally, the development of modified nanoparticles with a better hfetime and activities for various applications in catalysis remains an important challenge. Several recent investigations have made possible interesting results in various research areas around soluble nanoparticles synthesis, characterizations and their applications. In this context, total, partial or selective arene hydrogenations have received considerable attention and could still be... 

Finally, the development of modified nanoparticles having better stability and a longer lifetime has involved interesting results in diverse catalytic reactions. Efficient activities are obtained with these transition-metal colloids used as catalysts for the hydrogenation of various unsaturated substrates. Consequently, several recent investigations in total, partial or selective hydrogenation have received significant attention. 

CD-modified nanoparticles sites. These studies afford an interesting example of tunable catalyst design at the molecular level. Manipulation of the surface of cat-alytically active metal nanoparticles seems possible, and can be used to modulate the catalytic activity on demand. 

Solvent methods are similar to in situ polymerizations. During the first stage, the nanomaterial is dispersed in a solvent. In some cases a surfactant can be used as a bridge between the nanomaterials and the matrix (Fig. 4.9). This reaction occurs in a liquid or gel form in the presence of a solvent such as toluene, chloroform, acetonitrile, water, acetone, etc. The solution of modified nanoparticles is then added to a polymeric solution under agitation (at room or elevated temperatures) in order to ensure a homogeneous dispersion of the nanomaterials in the matrix. Finally, the polymer composite... 

This tin-modified nanoparticle of platinum is totally selective for isobutene. For example, when the Sn/Pts ratio is equal to 0.85, the selectivity to isobutene reaches... 

Very recently Beer and co-workers have developed a surface-enhanced optical anion sensor based on gold nanoparticles [78]. Dodecanethiol-stablised gold nanoparticles were modified by ligand substitution with a disulphide-substituted zinc porphyrin 113 to provide 30 and 80 receptors per nanoparticle. Titration of both the free receptor and the modified nanoparticles with various... 

Chapter 9 Modified Nanoparticles as Nanoelectrocatalysts and Amplifying Sensors... 

Huskens et al. exploited host-guest interactions between dendritic guest molecules and CD-modified nanoparticles for the formation of organic/metal nanoparticle multilayers on a PDMS stamp (Fig. 13.15).88 The multilayer stacks were transferred to a complementary host surface, while no materials remained on the protruding areas of the PDMS stamp. These multilayers showed a well-defined thickness control of 2 nm per bilayer. 

Park S-J, Lazarides AA, Mirkin CA, Letsinger RL. Directed assemble of directed materials from protein and oligonucleotide-modified nanoparticle building blocks. Angew Chem Int Ed Eng 2001 40 2909-12. 

Recently it has also been shown that modified spherical nanosilica particles can be used to toughen epoxy resins without the loss of other properties, such as glass transition temperature or modulus.28 When such surface modified nanoparticles are added to CTBN toughened epoxy resins, the performance of both one- and two-component epoxy adhesives was greatly improved. 

Oligonucleotides have frequently been used in the construction of nanodevices where they are used as a means of detection, as electrical wires or as a scaffold (see also section on nanodevices in section 3.5). A real-time DNA detection method using ssDNA-modified nanoparticles and micropatterned chemoresponsive diffraction gratings has been reported that allows hybridisa-... 

X-ray photoelectron spectroscopy (ESCA) can be use to determine the chemical composition of the nanoparticle surface. This technique is a very useful tool for the development of surface modified nanoparticles providing a direct evidence of the presence of the components that are believed to be on the nanoparticle surface. ... 

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