Nanoparticles coating

Moreover, stable liquid systems made up of nanoparticles coated with a surfactant monolayer and dispersed in an apolar medium could be employed to catalyze reactions involving both apolar substrates (solubilized in the bulk solvent) and polar and amphiphilic substrates (preferentially encapsulated within the reversed micelles or located at the surfactant palisade layer) or could be used as antiwear additives for lubricants. For example, monodisperse nickel boride catalysts were prepared in water/CTAB/hexanol microemulsions and used directly as the catalysts of styrene hydrogenation [215]. 

Mixtures of a nematic liquid crystal (LC or LC ) with small quantities of gold nanoparticles coated with alkylthiolates (<5 wt%) including an alkylthiolate functionalized with a chiral group have been studied (Figure 8.29) [72]. All mixtures show nematic mesophases with transition temperatures and phase stability very similar to those oftheliquid crystal precursors LC or LC. The introduction ofachiral center into the mixtures (mixtures of Au ) produce chiral nematic mesophases. A similar result is obtained in mixtures of Au and LC doped with the chiral dopant (s)-Naproxen. 

Additional experiments were carried out to study the behavior of Pd nanoparticles coated with Pt or with Pt plus M, which more closely reflects the morphology of actual catalyst particles. Figure 9.18a displays the polarization curves for the ORR on commercial carbon-supported Pt nanoparticles (Pt/C), Pd nanoparticles (Pd/C), a monolayer of Pt on Pd/C (PtMu/Pd/C), and mixed (Pto.gIro.a/ML/Pd/C and... 

Salkar RA, Jeevanandam P, Kataby G, Arana ST, Koltipin yuri, Palchik O, Gedanken A (2000) Elongated copper nanoparticles coated with a zwitterionic surfactant. J Phys Chem B 104 893-897... 

Ataman-Onal Y, Munier S, Ganee A et al (2006) Surfactant-free anionic PLA nanoparticles coated with HIV-1 p24 protein induced enhanced cellular and humoral immune responses in various animal models. J Control Release 112 175-185... 

On a larger scale, it is possible to store charge in gold nanoparticles. Chen described 1.8 nm diameter nanoparticles coated with a layer of alkylthiols,... 

Shopova, S. I., Nanoparticle Coated Optical Microresonators for Whispering Gallery Lasing and Other Applications, PhD dissertation, Oklahoma State University, 2007... 

Cassagneau, T. and Caruso, F., Continuous silver nanoparticle coatings on dielectric spheres, Adv. 

A 2 1-fold increase in fluorescence intensity was demonstrated for the long-wavelength hydrophilic bis-trimethine label 29 (original silver nanoparticles coated with a cryolite spacer [96], A 20-fold increase of fluorescence intensity and a sixfold decrease of the mean decay time were obtained for heptamethine cyanine dye 30 on silver nanoparticles [97],... 

Palladium nanoparticles coated with a fluorous-derivatized surfactant (or stabilizer) have been used to catalyse Heck and Suzuki reactions in a C8F17Br-benzene biphase [11], The reaction between phenylboronic acid and cinnamyl bromide was investigated and the reaction is illustrated in Scheme 10.10. 

Na K, Kim S, Park K, Kim K, Woo DG, Kwon IC, Chung HM, Park KH (2007) Heparin/poly(L-lysine) nanoparticle-coated polymeric microspheres for stem-cell therapy. J Am Chem Soc 129 5788-5789. 

Fig. 7.8 TEM images of the Si SiOx/C nanocomposite nanoparticles produced by hydrothermal carbonization of glucose and Si and further carbonization at 750 °C under N2. (a) Overview of the Si SiOx/C nanocomposites and a TEM image at higher magnification (in the inset) showing uniform spherical particles (b) HRTEM image clearly showing the core/shell structure (c), (d) HRTEM image displaying details of the silicon nanoparticles coated with SiOxand carbon.

Spherical gold nanoparticles coated with poly(N-isopropylacrylamide) (PNIPAM) grafts have been synthesized by controlled radical polymerization. The polymerization of N-isopropylacrylamide was initiated from the surface of the nanoparticles modified with 4-cyanopentanoic acid dithiobenzoate for reversible addition-fragmentation chain-transfer polymerization. The mean diameter of the Au core was 3.2 nm, as observed by means of high-resolution transmission electron microscopy [90]. 

Gold nanoparticles coated by short thiol end functional polystyrene homopolymers (PS-SH) can be incorporated into a poly(styrene-fo-2-vinylpyridine) diblock copolymer template (PS-NP2VP). It has been found that the surface density of PS chains on the gold particles is critical in controlling their location in block copolymer templates [95]. 

Fig. 17 Spindle-like hematite (10) [534] and anatase (11) [533] nanoparticles coated with calamitic liquid crystals...

Eby DM, Luckarift HR, Johnson GR (2009) Hybrid antimicrobial enzyme and silver nanoparticle coatings for medical instruments. ACS Appl Mater Interfaces 1 1553-1560... 

Similar results to these were found by Schwarz and Schonhoff [110] on nanoparticles coated by the PEM composed of poly(allylamine) (PAA) and PSS via XH NMR relaxation measurements. There, an increased water immobilization is reported for all odd polycation (PAA) terminating PEMs in contrast to even polyanion (PSS) terminating PEMs, which was found to be not just a property of the last adsorbed layer but more of the whole multilayer phase. 

In [18], we generated such excess electrons in a semiconductor colloidal CdS nanoparticles coated with thioglycerol by a short ( 5 ps) flash of light. In this case, photogenerated holes were rapidly (for the time less than the resolution of our devices) transferred to thioglycerol molecules. 

S. Lefebure, C. Menager, V. Cabuil, M. Assenheimer, F. Gallet, and C. Flament, Langmuir monolayers of monodispersed magnetic nanoparticles coated with a surfactant, J. Phys. Chem. B 102, 2733-2738 (1998). 

Caruso, R. A. Susha, A. Caruso, F. Multilayered Titania, Silica, and Laponite Nanoparticle Coatings on Polystyrene Colloidal Templates and Resulting Inorganic Hollow Spheres. Chem. Mater. 2001,13,400-409. 

Landry, F. B., Bazile, D. V., Spenlehauer, G., Veillard, M., and Kreuter, J. (1998), Peroral administration of 14C-poly(D,L-lactic acid) nanoparticles coated with human serum albumin or polyvinyl alcohol to guinea pigs,/. Drug Target., 6(4), 293-307. 

Raw nanomaterials Nanoparticle coatings Nanocrystalline materials Nanostructured materials Cyclic peptides Dendrimers Detoxification agents Fullerenes... 

Bonini, M., et al. (2006), Synthesis and characterization of magnetic nanoparticles coated with a uniform silica shell, Mater. Sci. Eng., 26(5-7), 745-750. 

Caruso, R.A., Susha, A. and Caruso, F., Multilayered titania, silica and laponite nanoparticle coatings on polystyrene colloidal templates and resulting inorganic hollow spheres, Chem. Mater. 13 (2001), pp. 400-409. 

Figure 6.36. Schematic of the formation of gold nanoparticles coated with free-radical polymerization initiators that subsequently yield Au polymer nanostructures through a surface-controlled living polymerization process. Reproduced with permission from Ohno, K. Koh, K.-M. Tsujii, Y Fukuda, T. Macromolecules 2002, 35, 8989. Copyright 2002 American Chemical Society.

Let us take for example the case of a metallic nanoparticle coated with a 10 nm dielectric spacer. The non-radiative emission is then typically negligible and Miot he order of Mh a- Maad exhibit a strong... 

Using this method to form a nanoparticle coated surface allowed us to better control the size of the nanostructures, but still generated a random distribution of nanoparticles. The density of silver nanostructures could be controlled by both the amount of time the substrate was immersed in the colloidal solution and the concentration of the colloidal solution. Because the size of the metal structures is directly determined by the colloids, sparse to densely packed colloid coated surfaces that maintain a unique metal nanostructure size could be produced by simply varying the incubation time in the colloid solution. 

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