Nanoporous channels

Hatori, H., H. Takagi, and Y. Yamada, Gas separation properties of molecular sieving carbon membranes with nanopore channels, Carbon, 42, 1169-1173, 2004. 

Porous chalcogenide aerogels is another broad class of non-oxidic framework that prepared by template-free routes [71-73]. These materials possess a continuous nanostructured chalcogenide framework that is penetrated by a random network of nanopore channels. Because these high surface area structures are random and not exhibit long-range pore periodicity, such systems are outside of the scope of this review and will not be covered further. 

Chang H et al (2004) DNA-mediated fluctuations in ionic current through silicon oxide nanopore channels. Nano Lett 4 1551-1556... 

Shin, Y.S. Liu, J. Wang, L.Q. Nie, Z.M. Samuels, W.D. Fryxell, G.E. Exarhos, G.J. Ordered hierarchical porous materials towards tunable size- and shape-selective microcavities in nanoporous channels. Angew. Chem. Int. Ed. Engl. 2000, 39, 2702-2707. Katz, A. Davis, M.E. Molecular imprinting of bulk, microporous silica. Nature 2000, 403, 286-289. 

Dendrimers are a category of macromolecules that have a central core surrounded by hyperbranched repetitive units. Dendrimers have versatile structures and chemical properties because the core, the branches, and the external surface can have different functions. The hyperbranched structure of dendrimers distinguishes them from other macromolecules or polymers. For example, dendrimers have large number of end groups as well as higher concentrations of nanoporous channels and cavities because the number of dendrimer end groups increases faster than the surface area. 

S independent electrodes aligned with the nanopore channel, e.g. for tunnelling detection or... 

Tim Albrecht, Marco Carminati, Giorgio Ferrari, Philippa Nuttall, William Pitchford and Agnieszka J. Rutkowska An introduction to nanopore sensing Ion and fluid transport in nanopore channels Low noise electronics for nanopore sensors Experimental impedance characterisation of solid-state nanopore sensors... 

Gies FI, Marler B and Werthmann U 1998 Synthesis of porosils crystalline nanoporous silicas with cage- and channel-like void structures Moiecuiar Sieves Science and Technoiogy vo 1, ed FI G Karge and J Weitkamp (Berlin Springer) pp 35-64... 

U. (1998) Synthesis of porosils Crystalline nanoporous silicas with cage-and channel-like void structures in Molecular Sieves Science and Technology, vol. 1 (eds H.G.Karge and ). Weitkamp), Springer, Heidelberg, pp. 35-64. 

Figure 2.52 2-D model of a counter-current heat-exchanger reactor with a nanoporous catalyst layer deposited on the channel wall.

A nanoporous structure on the surface of the micro channels can be realized via anodic oxidation, thereby considerably enlarging the catalyst surface [17]. Catalysts... 

P 17] In order to have a catalyst with a sufficiently high specific surface area, pretreatment of the micro channels made of aluminum was necessary [17], Following a cleaning procedure, an oxide layer with a regular system of nanopores was generated by anodic oxidation (1.5% oxalic acid 25 °C 50 V DC 2 h exposure using an aluminum plate cathode followed by calcination). 

Second, following a cleaning procedure with formalin, wet-chemical impregnation with palladium was performed [17]. The micro channels were exposed to a solution of 200 mg of PdCl2 in 40 ml of distilled water for 5 h. The PdCl2 was reduced to elemental Pd by formalin still present in the nanopores of the oxide layer which were generated one step before. This was followed by calcination. 

In order to see how the electrode thickness might be optimized in order to provide the lowest electrode resistivity, we have developed a theoretical model to describe the charge/discharge processes in porous carbon electrodes. As a first approximation, let us consider an electrode having two sets of cylindrical pores, namely, nanopores (NP) of less than 3 nm in diameter and transport channels (TC) of more than 20 nm in diameter, with each nanopore having an exit to only one TC. ... 

Figure 1. Model presentation of a few nanopore tiers facing a transport channel.

Fig. 9 Schematic representation of three approaches to generate nanoporous and meso-porous materials with block copolymers, a Block copolymer micelle templating for mesoporous inorganic materials. Block copolymer micelles form a hexagonal array. Silicate species then occupy the spaces between the cylinders. The final removal of micelle template leaves hollow cylinders, b Block copolymer matrix for nanoporous materials. Block copolymers form hexagonal cylinder phase in bulk or thin film state. Subsequent crosslinking fixes the matrix hollow channels are generated by removing the minor phase, c Rod-coil block copolymer for microporous materials. Solution-cast micellar films consisted of multilayers of hexagonally ordered arrays of spherical holes. (Adapted from [33])...

The nanoreplication of functional nanostructures has also been achieved through other block copolymer-templated structures. De Boer et al. [35] applied honeycomb-structured films of rod-coil block copolymer as patterned templates to replicate hexagonally packed arrays of aluminum cups on the substrate surfaces (Fig. 10b). Nguyen et al. [237] embedded semiconducting polymers in the channels of oriented hexagonal nanoporous silica and used this nanoscale architecture to control the energy transfer for potential optoelectronic applications. 

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