The growth of silver nanoparticles, the activation energy for silver particle growth, and the release of silver species in heat treated SiO 2 -Ag composite powders are investigated. The silver particle growth is controlled by heat treatment for 75 min of the as-synthesized SiO 2 -Ag composite powder at 300-800 °C. During heat treatment the mean size of the Ag particles increases from 10 nm up t...

This study deals with bioleaching of the low grade uranium ore of Saghand mine in Iran using a mixed culture of mesophilic bacteria (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans). Experiments were carried out in shaking flask examining the effect of temperature, initial ferrous ion concentration, pulp density and particle size. Variations of ...

Zhang et al. (2005) present a parameterization for what they term the "growth factor" of a sea salt aerosol particle relative to its formation diameter, which they assert "is a function of relative humidity alone" and independent of an arbitrary reference relative humidity. Here we note that this growth factor implicitly assumes an arbitrary reference relative humidity through the salinity of t...

Measurements on the composition of nanometersized atmospheric particles are the key to understand which vapors participate in the secondary aerosol formation processes. Knowledge on these processes is crucial in assessing the climatic effects of secondary aerosol formation. We present data of >2 nm particle concentrations and their water-affinity measured with the Condensation Particle Counter ...

Consistency of the Bekenstein bound on entropy requires the physical dimensions of particles to grow with momentum as the particle is boosted to transplanckian energies. In this paper the problem of particle growth in heterotic string theory is mapped into a problem involving the properties of BPS saturated black holes as the charge is increased. Explicit calculation based on the black hole sol...

The relation between the multiplicity growth and the energy loss spectrum of an incident particle, as implied by Poisson emission with a classical spectrum, appears to be obeyed experimentally in PP collisions. (Submitted to Phys. Rev. Letters) * Work supported by the U. S. Atomic Energy Commission. The Brookhaven experiments’ on the behavior of the final proton in highly inelastic PP collision...

Particle aggregation with simultaneous surface growth was modeled using a dynamic Monte Carlo method. The Monte Carlo algorithm begins in the particle inception zone and constructs aggregates via ensemble-averaged collisions between spheres and deposition of gaseous species on the sphere surfaces. Simulations were conducted using four scenarios. The first, referred to as scenario 0, is used as ...

Introduction Conclusions References Tables Figures Back Close Abstract Introduction Conclusions References Tables Figures Back Close Abstract The formation and growth of atmospheric aerosol particles is considered using an exact discrete method with molecular resolution in size space. The method is immune to numerical diffusion problems that are a nuisance for typical simulation methods using a...

Submicron to micron size particles are produced in the gas phase of sputtering discharges. These particles can contaminate thin films grown by sputter deposition. On the other hand, particle production in a discharge can be desirable when used for manufacturing fine powders. Here, experimental results are presented demonstrating particle production in an argon discharge, using a variety of targ...

An inverse modeling procedure to determine particle growth and nucleation rates from measured aerosol size distributions B. Verheggen and M. Mozurkewich Department of Chemistry and Centre for Atmospheric Chemistry, York University, Toronto ON M3J 1P3, Canada now at: Laboratory for Atmospheric Chemistry, Paul Scherrer Institute, 5232 Villigen PSI, Switzerland Received: 7 December 2005 – Accepted...