UNTITLED - REPLY

Quantum mechanical calculation of ethylene hydrogenation on nickel 111 single crystal surface and nickel nanoclusters

Sayar, Aslı; Önal, Işık; Department of Chemical Engineering (2005)

Ethylene hydrogenation on Ni(111); equilibrium geometry calculations for Ni2 dimer, Ni13 and Ni55 nanoclusters; and ethylene adsorption on Ni(100), Ni(111), Ni2, and Ni13 were studied quantum mechanically by means of energetic and kinetic differences. Ethylene hydrogenation on Ni(111) was simulated by use of DFT/B3LYP/6-31G** formalism. The reaction mechanism was mainly composed of three elementary steps. Firstly, ethylene adsorption on bare Ni(111) surface was performed. Second step and third step were the...
Numerical simulation of radiating flows Karaismail, Ertan; Selçuk, Nevin; Department of Chemical Engineering (2005) Predictive accuracy of the previously developed coupled code for the solution of the time-dependent Navier-Stokes equations in conjunction with the radiative transfer equation was first assessed by applying it to the prediction of thermally radiating, hydrodynamically developed laminar pipe flow for which the numerical solution had been reported in the literature. The effect of radiation on flow and temperature fields was demonstrated for different values of conduction to radiation ratio. It was found that ...
Numerical simulation of laminar reaction flows Tarhan, Tanıl; Selçuk, Nevin; Department of Chemical Engineering (2004) Novel sequential and parallel computational fluid dynamic (CFD) codes based on method of lines (MOL) approach were developed for the numerical simulation of multi-component reacting flows using detailed transport and thermodynamic models. Both codes were applied to the prediction of a confined axisymmetric laminar co-flowing methane-air diffusion flame for which experimental data were available in the literature. Flame-sheet model for infinite-rate chemistry and one-, two-, and five- and ten-step reduced fi...
Impact modified polystyrene based nanocomposites Yeniova, Canan Esma; Yılmazer, Ülkü; Department of Chemical Engineering (2009) Polystyrene, PS, is a preferable polymer in industry, but, its brittle characteristic restricts its utilization. The aim of this study is to improve the impact strength of PS by the help of elastomeric materials SEBS-g-MA and E-BA-GMA. In order to prevent the reduction in the tensile strength of the materials, three different types of organic montmorillonites, MMT, (Cloisite® 30B, 25A and 15A) were used as fillers. Nanocomposite preparation was performed in a co-rotating twin screw extruder. Initially elast...
Mathematical modeling of nox emissions in bubbling fluidized bed combustors Afacan, M. Onur; Selçuk, Nevin; Department of Chemical Engineering (2005) A comprehensive model, previously developed and tested for prediction of behavior of continuous fluidized bed combustors is extended to incorporate NOx formation and reduction reactions and applied to the simulation of METU 0.3 MWt Atmospheric Bubbling Fluidized Bed Combustor (ABFBC) burning lignites with high volatile matter in their own ashes. The predictive accuracy of the model was assessed by comparing its predictions with measurements taken previously on the same rig. Favorable comparisons are obtaine...

Citation Formats

T. MEHMETOGLU and H. GUCUYENER, “UNTITLED - REPLY,” 1994. Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/65331.