Dispersion nanometer-scale

Information on the morphology of the nanohybrid sorbents also was revealed with SEM analysis. Dispersed spherical polymer-silica particles with a diameter of 0.3-5 pm were observed. Every particle, in one s turn, is a porous material with size of pores to 200 nm and spherical particles from 100 nm to 500 nm. Therefore, the obtained samples were demonstrated to form a nanometer - scale porous structure. 

Colloidal dispersions of fine metal particles have a long history. Metal nanoparticles are now in the spotlight because of recent developments in nanometer-scale science and technology. Especially the precise structure of the monodispersed bimetallic nanoparticles has become clear quite recently, thanks to the development of EXAFS technology. The mechanism of formation, growth, and structure control is not completely clear yet. In some parts, especially in Section 9.1.4, the discussion may be speculative but is based on the experience of the present author for over 20 years. 

The key to most of the functional properties reported is a fine microstructure of the metal particles (i.e. in the nanometer scale) which is uniformly dispersed within a ceramic matrix. In some cases the particle size needed is in the range of a few nanometers in order to enhance the surface properties, while in other cases optimization is needed between the demand for single domain particles while minimizing unwanted surface states. 

An interpretation of the results for catalytic reaction kinetics on active supported nanoparticles on the scale down to 10nm has been obtained by the MC technique [285]. The technique allows the peculiarities of the reaction performance on the nanometer scale, including the inherent heterogeneity of metal crystallites as well as spontaneous and adsorbate-induced changes of the shape and degree of dispersion of supported catalysts. 

Lipospheres were first reported by Domb, who described them as water-dispersible solid microparticles of a particle size between 0.2 and 100 pm in diameter, composed of a solid hydrophobic fat core stabilized by a monolayer of phospholipid molecules embedded in the microparticles surface [1], Using this definition, lipo-sphere size is on the nanometer scale. Usually, nanoscale particles consisting of a solid lipid core are termed SLN [16], though sometimes inconsistent nomenclature can be found. Unlike SLN, lipospheres are restricted to the stabilizing material of a phospholipid layer because of their definition [1], This chapter focuses on research results obtained for peptide and protein formulations termed lipospheres, and it does not consider SLN literature at large. 

The aim of this work is testing of SERS-activity of metal-containing microporous alumosilicates or zeolites. Porous structure of zeolite skeletons caused by coupling of tetrahedral [Si04] and [AIO4] building units is a unique basis for stabilization of a super-lattice of mono-dispersed metal clusters. Zeolite matrices combine the factors of nanoporosity and nanometer-scale chemical reactivity with respect to incorporated foreign ions, clusters, and nanoparticles [1]. 

Nanometer Scale Surface-induced Coating of the Precursor for the Dispersed ZrC>2 Phase... 

The recent progress in polymer synthesis and nanotechnology is stimulating the development of adhesives with improved performance. A few percent of nanometer-scale additives can be added to formulations in order to achieve significant changes in property profiles. Molecular nanoparticles and nanometer-scale, highly branched polymers can be dispersed in order to facilitate energy dissipation at the crack tip by means of multiple plastic deformation. The self assembly of nanoparticles forms skeleton-like superstructures which account for... 

Ultrasound irradiation has been used in the process of catalyst preparation. Acoustic irradiation increases the dispersion of the active metal on the support,depassivates the metal, and reduces the particle size to nanometer scale.In the case of palladium supported on active carbon prepared under ultrasound with extremely high surface area, not only was a greater metal dispersion achieved, but a larger penetration of metal inside the pores of the support and an easier elimination of chloride ion were observed as well. ... 

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