Multi-hollow structure

PMMA particles with hollow structures were synthesised by water-in-oil-in-water emulsion polymerisation. Sorbitan monooleate was used as a primary surfactant and sodium lauryl sulphate and Glucopen (a polypeptide derivative) were used as secondary surfactants. Urethane acrylate, with a hard segment in the molecular backbone, a long soft segment in the middle and vinyl groups at both ends was used as a reactive viscosity enhancer. Only a few particles contained a void in the polymer phase at low concentrations of urethane acrylate, but as the concentration of urethane acrylate increased, so did the number of particles containing the void. This was because urethane acrylate increased the viscosity of the monomer mixture and helped to form the stable emulsion droplets. At concentrations of urethane acrylate above 7 wt%, multi-hollow structured particles were produced. The mechanism of formation of the hollow particles was discussed. 7 refs. 

A series of multi-hollow structure core-shell latex particles in the presence and absence of acrylic acid was synthesised by seeded emulsion copolymerisation, then... 

The main difference between titania nanotube and the ID nanostructures discussed before is the presence of an hollow structure, but which has significant consequences for their use as catalytic materials (i) in the hollow fiber nanoconfinement effects are possible, which can be relevant for enhancing the catalytic performance (ii) due to the curvature, similarly to multi-wall carbon nanotubes, the inner surface in the nanotube is different from that present on the external surface this effect could be also used to develop new catalysts and (iii) different active components can be localized on the external and internal walls to realize spatially separated (on a nanoscale level) multifunctional catalysts. 

Hollow tubular single or multi walled structures, with wall thickness of 0.07 nm and interlayer spacing of 0.34 nm. 

In traditional microwave systems antennae are fabricated on rigid substrates, as wires or as hollow structures. Antennae on textiles have been demonstrated earlier but only with limited design variations, mainly as microstrip patch or slot antennae. There is a need to explore different structures especially in view of multi-fiequency or wideband operation. 

They are FDA and USDA approved for direct food contact. They are also acceptable for direct food contact in Canada. EVAL resins are non-toxic and can be recycled for use in multi-walled structures. EVAL resins can be used in retortable food containers. Hiey are also used to produce hollow fibers for kidney dialysis machines. 

Five years after the discovery of fullerenes, Iijima reported in 19911 a novel form of organized carbon which consists of hollow cylindrical structures, a few nanometers in diameter and some micrometers long. Although hollow carbon nanofibers had been prepared for several decades, their walls had never been resolved by High-Resolution Transmission Electron Microscopy (HRTEM). These HRTEM images allowed Iijima to conclude that the walls of the so-called multi-walled carbon nanotubes (MWCNTs) are made up of several concentric cylinders, each being formed by a graphene sheet rolled... 

In this work, two support shapes are of particular interest tubular and flat supports, which are currently the most used supports in membrane research. Apart from these shapes also ceramic multi-bore tubes and honeycomb structures are produced for membrane applications and recently a-alumina hollow fibre supports were developed as well [1],... 

In HRTEM the carbon nanotubes appeared as long fibers, [12,90-95] (Fig. 20) with diameters ranging from about 1 to many tens of nanometers. They are hollow and clearly graphitic, as evidenced from the layered structure with an interlayer spacing close to that of bulk graphite and from diffraction studies of the individual cylindrical layers or tubules [12]. These layered nanotube structures are called multi-walled carbon nanotubes (MWNTs) The tubes are closed at the end each tubule appears to close on itself and hence the entire structure resembles a Russian doll. 

Cao Jiang, 2007), wire-in-tube structures (Greiner Wendorff, 2007), What s more, twisted fiber bundles, golfball-like micro particles and multi-chambered hollow spheres (Chen et al., 2008) are also able to be generated via this technique. These fibrous structures and particles obtained by electrospinning have some unmatchable properties, like the... 

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