In this study the catalytic dehydrogenation of ethylbenzene to styrene was investigated in a simulated tubular sodalite membrane reactor. The high quality microporous sodalite membrane was synthesized by direct hydrothermal method and characterized by single gas permeation measurements. The performance of the prepared membrane showed high potential for application in a dehydrogenation membrane ...

The accumulation of defects, and in particular He bubbles, can have significant implications for the performance of materials exposed to the plasma in magnetic-confinement nuclear fusion reactors. Some of the most promising candidates for deployment into such environments are nanocrystalline materials as the engineering of grain boundary density offers the possibility of tailoring their radiati...

This paper describes the properties of nanocrystalline silver products (Acticoat) and their applications and examines available evidence supporting their use in wound management. Acticoat utilizes nanotechnology to release nanocrystalline silver crystals. Acticoat releases 30 times less silver cations than silversulfadiazine cream or 0.5% silver nitrate solution but more of the silver released ...

Class F Fly ash-based geopolymers are prone to various high-temperature phenomena, such as cracking, spalling, and thermal shrinkage. Here we study the effect of enriching fly ash with synthetic sodalite phase in order enhance properties formed geopolymer. The morphological changes, compositional alterations porosity, gel behaviour, on deformation material after exposure up 1000 °C investigated...

OBJECTIVES SUS 304 stainless steels have been widely used in orthodontics and implants such as archwires, brackets, and screws. The purpose of present study was to investigate the biocompatibility of both the commercial microcrystalline biomedical 304 stainless steel (microcrystalline 304ss) and novel-fabricated nanocrystalline 304 stainless steel (nanocrystalline 304ss). METHODS Bulk nanocry...

Removal of arsenate (As(V)) from aqueous solution using both nanocrystalline and coprecipitated Mg/Al layered double hydroxides (LDHs) was examined under different sorption/desorption conditions. The surface area, pore volume, and pore size of the nanocrystalline LDH were significantly higher than those of the coprecipitated LDH, thus resulting in a higher As(V) sorption maximum than the coprec...

X-ray powder methods have been used to study the room-temperature structures of the synthetic sodalites: Li8(AI6Si6024)CI2, KT.6Nao.4(A16Si6Oz4)CI2, and Nas(A16Si6024)I ~. Natural sodalite was also studied and the atomic coordinates show satisfactory agreement with those determined from the single-crystal data of L6ns and Schulz (1967). The LiC1and KCIas well as the NaCl-sodalites refined in th...

A genetic algorithm has been used to generate crystal framework structures, including that of sodalite and chabazite, from the knowledge of only the unit cell dimensions, constituent elements and by defining exclusion zones–regions within the unit cell where the constituent elements are forbidden, as opposed to being discouraged. We present details of a direct approach to restricting the possib...

We have investigated various silica zeolites using density functional theory with periodic supercells, plane waves, and pseudopotentials. These zeolitic phases include silica sodalite, chabazite, mordenite, silica LTA, and silicalite. Atom-level geometries, elastic properties, and cohesive energies are presented. Although the zeolites exhibit a wide range of Si-O-Si angles and densities, the co...