Nanostructured phases

However, a strictly defined model of such system formation does not currently exist. To further study the problem of nanostructure phase-formation the methodology of P-parameter is applied in this paper. 

Mesostructured aluminophosphate / surfactant composite materials were prepared from aqueous and alcoholic systems. Syntheses in ethanol or methanol, respectively, lead to mixtures of two nanostructured phases. One of these consists of hexagonally arranged rod-like assemblies of the surfactant molecules with the head groups located in the centres, encapsulating the inorganic aluminophosphate the other is lamellar. The syntheses were monitored by in-situ temperature- and time-resolved small angle X-ray scattering (SAXS). 

The development of composite structural materials based on ordered nanostructures in a matrix material has been surprisingly difficult to accomplish, and has only proved successful in a few cases165. Part of the difficulty is that the surface chemistry of the nanostructures must be controlled carefully so that the structure truly is a composite and that the nanostructured phase in the matrix is ordered. Given the importance of nano-scale heterogeneity in determining the mechanical properties of materials, this area is one of great theoretical and practical interest. 

Walker et al. (1989) Ce-Ru, Ce-Co, Ce-Fe Nanostructuring, phase segregation + + + Ammonia synthesis on alloy catalysts... 

The synthesis of lithium aluminates for tritium production requires formation of nanostructured phases. These can be made by solid-state reaction, by appropriate mixing of oxide powders [84] or by sol-gel methods [80, 85-87], One technique is the peroxide route where y-Al203 and LiC03 are dissolved in a peroxide (H202) solution. Evaporation of water and calcining the solid residue results in nanophase LiA102. 

Fig. 4 Schematic of a highly porous nano structured electrode protruding from a current collector, a Nanoflber structure or a template-like membrane, and b spherical-like particle-based nanostructure. Note that real nanostructures are not so regular, but both nanostructured phase and electrolyte, as discussed herein, are continuous along the length L [113], The length L determines if the nanostructured electrode will be considered 2-D or 3-D and is very important in modeUng electronic and ionic transport in the nanostructured electrode [86,113]...

N.A.M. Shanid, M.A. Khadar, Evolution of nanostructure, phase transition and band gap tailoring in oxidized Cu thin films. Thin Solid Films 516, 6245-6252 (2008)... 

Fig. 25 Monomer density plots of the 21 nanostructured phases formed in a cylindrical pore with a Dp-value of 17 times the radius of gyration. The color ranges from deep red (A-rich regions) to deep blue (B-rich regions). The region outside the cylindrical pore is also colored deep blue. The notation C is used for qdindrical phases, L for lamellar phases, and LC for structiu es containing both lamellae and cylinders (intermediate structure). When the cylinders are composed of minority B component, an overbar is used. The number of cylinders in each ring, out from the center of the pore, is indicated by subscripts The number of L subscripts in the notation LCi...i,i-j indicates the...

A weakly segregated rod-coil block copolymer system composed of poly(2,5-diethylhexyloxy-l,4-phenylene-vinylene) (DEH-PPV) rod blocks and PI coil blocks was used to map the equilibrium phase behavior with respect to temperature, molecular weight, and coil ffaction. The phase diagram is shown in Figure 17. These results show lamellar and hexagonal nanostructured phases and both nematic and isotropic phases where the rods and coils are miscible. 

These self-assembled systems include lamellar (La) and non-lamellar (two and three dimensional bicontinuous and discontinuous nanostructures) phases, and inverted type micellar solution (L2). 

Figure 1 - Sonolysis of metal complexes to various forms of nanostructured phases...

Related to these structures and also of relevance for the preparation of nanoparticles are some amphiphile-based nanostructured phases which do not possess any long range order. For example, another type of bicontinuous phase with relation to the inverse bicontinous cubic phases is the so-called sponge phase (L3). Its curved bilayer structure is disordered so that the water channels adopt a sponge-like structure. Sometimes this phase is referred to as a "melted cubic (v2) phase". Moreover, also dispersions of inverse micellar phases (L2) have been described which may be regarded as "melted I2 phase". Although such disordered phases do not represent a liquid crystalline phase in a strict sense they are included here since they are of relevance for nanoparticulate drug delivery purposes. 

Yavari F, Fard HR, Pashayi K, Rafiee MA, Zamiri A, Yu Z, et al. Enhanced thermal conductivity in a nanostructured phase change composite due to low concentration graphene additives. J Phys Chem C 2011 115 8753-8. 

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