We propose a novel island nucleation and growth model explicitly including transient (ballistic) mobility of the monomers deposited at rate F, assumed to be in a hot precursor state before thermalizing. In limiting regimes, corresponding to fast (diffusive) and slow (ballistic) thermalization, the island density N obeys scaling N∝F(α). In between is found a rich, complex behavior, with various ...

We present a rate-equation model for two-photon lasers that, despite its simplicity, captures the essential physics of their behavior and affords an intuitive understanding of their novel threshold and stability behavior. We use the model to investigate the steady-state behavior of the laser, explore the stability of the steady-state solutions, and predict the injected pulse strength needed to ...

With the advancement of nanoscale semiconductor technology,semiconductor optical amplifiers are used to amplify and process all-optical signals. Inthis paper, with the aim of calculating the gain of quantum dot semiconductor opticalamplifier (QD-SOA), two groups of rate equations and the optical signal propagatingequation are used in the active layer of the device. For t...

A new simple analytical model for prediction of cooling rate in the solidification process based on the local heat flux density extracted during solidification is introduced. In the modeling procedure, a solidifying control volume is considered in the mushy zone in which a heat balance equation is used to derive the present model. As the local heat flux density is a measurable parameter, the pr...

in this study, the longitudinal shrinkage behavior of knitted fabrics during drying has been studied. in this context, a model is presented to predict the longitudinal shrinkage of plain knitted fabric during drying process. in order to model the shrinkage behavior, a 1dof model consists of a mass, a linear spring and a linear damper have been used. in presented model the time-varying mass is c...

background and objectives: lactobacillus delbrueckii ssp bulgaricus is widely used in dairy industries as a starter for yogurt production. this study was designed using response surface methodology (rsm) in 12 batch ph-controlled cultures of lactobacillus delbrueckii sub-ssp. bulgaricus for determining the effect of temperature and ph on the biomass production of a native strain of l. bulgaricu...

We present and analyze a simple model based on six rate equations for an electrically pumped organic diode laser. The applies to host-guest systems includes Stoke-shifted reabsorption in self-consistent manner. With the validated Alq3:DCM system, we predict threshold short-pulse laser operation. operation characterized by damped relaxation oscillations GHz regime several orders of magnitude lin...

Effect of water gas shift reaction (CO+H2O=CO2+H2) on wustite reduction has been investigated by a transient, non-isothermal mathematical model based on grain model. In this model, wustite porous pellet is reduced using Syngas, namely a mixture of hydrogen, carbon monoxide, carbon dioxide and water vapor. For this purpose, governing equations containing continuity equation of species and energy...