Nano-sized pores

The investigation of the pore size distribution (Fig. 1) shows that nano-size pores (radius ca. 20 nm) predominate in the gas layer from this hydrophobic material. 

A classification of pores based on pore sizes was proposed by the International Union for Pure and Applied Chemistry (lUPAC). As illustrated in Fig. 1, pores are usually classified into three classes macropores (>50 nm), mesopores (2-50 nm) and micropores (<2 nm) [1], Micropores can be further divided into supermicropores (with a size of 0.7-2 nm) and ultramicropores (<0.7 nm in size), Since nanotechnology attracted the attention of many scientists recently, the pore structure has been required to be controlled closely, a part of which will be explained in Section 5. Wlten scientists wanted to express that they are controlling pores in the nanometer scale, some of them preferred to call the smallest pores nano-sized pores, instead of micro/mesopores. 

Development of extrinsic nano-sized pores in glass-like carbon spheres... 

Activated carbon is a porous carbon material with developed nano-sized pores and a high specific surface area (>1,000 m g ). Nowadays, the technical term nanoporous carbon is very often used to mean activated carbon, but the activated carbon should be strictly defined as a porous carbon prepared by an activation process consisting of a gasification reaction to form the developed nano-sized pore stmcture in the carbon matrix. The activated carbons have been widely utilized as industrial materials, for example, an adsorbent, decolorizing agent, deodorant, and catalyst. The details of the preparation method, pore structure, and applications of activated carbons have been described [1]. The most significant electrochemical application of activated carbons is use as an electrode active material for an electric double-layer capacitor (EDLC). This article reviews the use of activated carbons in an EDLC. 

Li, Z., Zhang, J., Du, J., Han, B., and Wang, J. 2006. Preparation of silica microrods with nano-sized pores in ionic liquid microemulsions. Colloids Surf. A 286, 117-120. 

The other difference between copper and tin electro-deposits is their microstracture. From the transmission electron microscope analyses, it proved that the branches of copper are a polycrystal-line structure, including a lot of nano-sized pores inside them, whereas the branches of tin are a single crystal without internal pores and grain boundaries. The poly crystallinity of copper branch is attributed to... 

As zeolitization of fly ash is a complex phenomenon. Fig. 6.18 intends to simplify complex effects of successive activations of the fly ash, in three-steps. In such a situation, grinding of a residue, may cause peeling off and crumbling the deposited crystals of the FAZ (refer Fig. 6.14) and thus exposes the roughened boundary of impurities, IMP from Step-1 and Step-2. In fact, the activated boundary contains many nano-sized pores, as observed in Fig. 6.14b-g, which... 

An excellent example of such a composite membrane type is represented by the work recently published by Tanaka et al. (2008). The starting material used for preparing the novel pore-filled palladium membrane was the YSZ supported on macroporous a-alumina. At this step, palladium particles could be successively deposited as a top layer of the YSZ-7-AI2O3 membrane (Fig. 3.10) or as nano-size pores of ceramic y-Al203 (Fig. 3.lid). 

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