Controlled release from protein particles encapsulated by molecular layer deposition

Molecular layer deposition (MLD) was used to coat micron-sized protein particles in a fluidized bed reactor. Our results show that the dissolution rate of particles coated via MLD rapidly decreases with the increase in number of coating cycles, while the uncoated particles dissolve instantaneously.

Gas-Phase Deposition of Ultrathin Aluminium Oxide Films on Nanoparticles at Ambient Conditions

We have deposited aluminium oxide films by atomic layer deposition on titanium oxide nanoparticles in a fluidized bed reactor at 27 ± 3 °C and atmospheric pressure. Working at room temperature allows coating heat-sensitive materials, while working at atmospheric pressure would simplify the scale-up of this process. We performed 4, 7 and 15...

Continuous production of nanostructured particles using spatial atomic

In this paper, the authors demonstrate a novel spatial atomic layer deposition (ALD) process based on pneumatic transport of nanoparticle agglomerates. Nanoclusters of platinum (Pt) of ?1?nm diameter are deposited onto titania (TiO2) P25 nanoparticles resulting to a continuous production of an active photocatalyst (0.12–0.31?wt. % of Pt) at a...

Multidimensionality in Fluidized Nanopowder Agglomerates

recent years, the interest in fluidization as a mean to process nanoparticles is strongly increasing. Due to the small size of the nanoparticles, which makes van der Waals forces predominate, they do not fluidize as single particles but as agglomerates. Various researchers using settling experiments and bed expansion measurements conclude that...

Dynamics of Single Rising Bubbles in Neutrally Buoyant Liquid-Solid Suspensions

We experimentally investigate the effect of particles on the dynamics of a gas bubble rising in a liquid-solid suspension while the particles are equally sized and neutrally buoyant. Using the Stokes number as a universal scale, we show that when a bubble rises through a suspension characterized by a low Stokes number (in our case, small...

Selectivity of the Fischer–Tropsch process: Deviations from single alpha product distribution explained by gradients in process conditions

Non-ASF product distributions in Fischer–Tropsch synthesis can occur with a gradient in process conditions at the particle or reactor scale, leading to a gradient in chain growth probability a.Weighted summation of local product distributions gives the proper, non-ASF product distribution.

Atomic layer deposition of platinum clusters on titania nanoparticles at atmospheric pressure

We report the fabrication of platinum nanoclusters with a narrow size distribution on TiO2 nanoparticles using atomic layer deposition. With MeCpPtMe3 and ozone as reactants, the deposition can be carried out at a relatively low temperature of 250 degrees C. Our approach of working with suspended nanoparticles at atmospheric pressure gives...

The role of the hydrogen bond in dense nanoparticle–gas suspensions

The effect of surface characteristics on the interaction between nanoparticles and their agglomeration in dense gas suspensions is still not fully understood. It is known that when the surface is covered with hydroxyl groups, the interaction between nanoparticles becomes substantially stronger than in the absence of these groups; this...

Fluidization of nanopowders: A review

Nanoparticles (NPs) are applied in a wide range of processes, and their use continues to increase. Fluidization is one of the best techniques available to disperse and process NPs. NPs cannot be fluidized individually; they fluidize as very porous agglomerates. The objective of this article is to review the developments in nanopowder...

Process and apparatus for producing coated particles

The invention is directed to a process and apparatus for preparing coated particles, in particular a process for preparing particles that are coated with small particles using electrospraying. The coated particles produced according to the present invention find use for instance as catalysts or as pharmaceuticals. According to the invention a...

Apparatus and process for atomic or molecular layer deposition onto particles during pneumatic transport

The invention provides a process for depositing a coating onto particles being pneumatically transported in a tube. The process comprising the steps of providing a tube having an inlet opening and an outlet opening; feeding a carrier gas entraining particles into the tube at or near the inlet opening of the tube to create a particle flow through...

Method for Covering Particles, Especially a Battery Electrode Material Particles, and Particles Obtained with Such Method and a Battery Comprising Such Particle

A method for covering particles having a diameter of maximally 60 mum by means of atomic layer deposition, whereby said method comprises the step of fluidizing said particles in a fluidized bed reactor using a first reactant gas comprising a first reactant for substantially completely covering said particles with a monolayer of said first reactant.

Measuring the gas-solids distribution in fluidized beds - a review

Bubble size reduction in a fluidized bed by electric fields

The reduction of the size of bubbles can improve both selectivity and conversion in gas-solid fluidized beds. Results are reported of the reduction of bubble size by the application of electric fields to uncharged, polarizable particles in fluidized beds. It is shown how average bubble diameters can be drastically reduced, with little change of...

Monitoring Fluidized Bed Hydrodynamics