Nano-entities

A key aspect of metal oxides is that they possess multiple functional properties acid-base, electron transfer and transport, chemisorption by a and 7i-bonding of hydrocarbons, O-insertion and H-abstraction, etc. This multi-functionality allows them to catalyze complex selective multistep transformations of hydrocarbons, as well as other catalytic reactions (NO,c conversion, for example). The control of the catalyst multi-functionality requires the ability to control not only the nanostructure, e.g. the nano-scale environment around the active site, " but also the nano-architecture, e.g. the 3D spatial organization of nano-entities. The active site is not the only relevant aspect for catalysis. The local area around the active site orients or assists the coordination of the reactants, and may induce sterical constrains on the transition state, and influences short-range transport (nano-scale level). Therefore, it plays a critical role in determining the reactivity and selectivity in multiple pathways of transformation. In addition, there are indications pointing out that the dynamics of adsorbed species, e.g. their mobility during the catalytic processes which is also an important factor determining the catalytic performances in complex surface reaction, " is influenced by the nanoarchitecture. 

Research in chemistry of materials for the past decades demonstrated that designing new architectures based on the nano-entities assembling may provide synergetic effects. 

The next three chapters (Chapters 9-11) focus on the deposition of nano-structured or microstructured films and entities. Porous oxide thin films are, for example, of great interest due to potential application of these films as low-K dielectrics and in sensors, selective membranes, and photovoltaic applications. One of the key challenges in this area is the problem of controlling, ordering, and combining pore structure over different length scales. Chapter 9 provides an introduction and discussion of evaporation-induced self-assembly (EISA), a method that combines sol-gel synthesis with self-assembly and phase separation to produce films with a tailored pore structure. Chapter 10 describes how nanomaterials can be used as soluble precursors for the preparation of extended... 

Notably, the use of heteronuclear surface carbonyl species can lead to the preparation of well-defined supported bimetallic entities that can be used as model catalysts to study the promoter effect of a second metal. The close intimacy achieved between the two metals in the surface carbonyl species is related to the structural characteristics and catalytic properties of the final catalyst In the preparation of supported, tailored, multi-component catalysts, the use of metal carbonyl surface species still deserves to be studied to further explore the exciting field of nano-sized entities in catalysis. 

In principle, the long-term stability can be greatly improved by replacing the internal (macro)emulsion by a wawoemulsion or, better still, a thermodynamically stable micro-emulsion. (We note that, in this context, the prefix micro denotes an entity that is smaller than nano )... 

The following review is concerned with the synthetic and structural chemistry of molecular alumo-siloxanes, which combine in a molecular entity the elements aluminum and silicon connected by oxygen. They may be regarded as molecular counterparts of alumo-silicates, which have attracted considerable attention owing to their solid-state cage structures (see for example zeolites).1 3 Numerous applications have been found for these solid-state materials for instance the holes and pores can be used in different separation techniques.4,5 Recently the channel and pore structures of zeolites and other porous materials have been used as templates for nano-structured materials and for catalytical purposes.6 9... 

Qzm and A50 have different affinities for BSA. Since the experiment was done at constant pH and ionic strength, the observed differences in the amount of BSA adsorbed, and the different conformation of BSA on the two silica dusts, is ascribed to the intrinsic properties of the two silica forms such as size and morphology (down to a micro- and nano level), surface hydrophilicity, impurities at the surface, and surface charge. Qzm and A50 particles are, in fact, very different entities they differ in particle dimensions (Qzm mean diameter 1600 nm, A50 40 nm) and bulk structure, which involves different surface features such as silanol population, (quartz exhibits around 5 SiOH/nm2, A50 2-3 SiOH/nm2), hydrophilicity, micromorphology (quartz particles exhibit steps and edges due to the grinding processes, fumed silica is made up by roundish particles) and the presence of metal ion impurities. 

Improved bioavailability. More than 40% of the NCEs (new chemical entity) discovered have good membrane permeability but poor aqueous solubility (i.e.. Biopharmaceutics Classification System II). By formulating the NCE in solution inside a Softgel (e.g., lipid based) or in micro/nano emulsion, the solubility and hence the bioavailability of the compound may be improved. ... 

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