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Full-Text Articles in Engineering

Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines Oct 2008

Homogeneous Dbd In N2: 1) Lif, Talif And Electrical Measurements, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines

Dr. Et-touhami Es-sebbar

In this paper we compare two different discharges that can be obtained in a DBD configuration, that is to say the filamentary discharge (usual regime in atmospheric DBD) with the Atmospheric Pressure Townsend Discharge (APTD), which is a homogeneous regime obtained in nitrogen atmosphere. The aim is to help in the understanding of the processes which control the transition from one regime to the other. To do so, the discharge is characterized through electrical measurements, coupled with optical diagnostics among which Laser Induced Fluorescence (LIF) for radical density measurements. The influence of the addition of small quantities of additives on …


Oscillating Regime In Carbonylation Reaction Of Propargyl Alcohol (In Russian), Sergey N. Gorodsky, Anatoly V. Kurdiukov, Oleg N. Temkin Sep 2008

Oscillating Regime In Carbonylation Reaction Of Propargyl Alcohol (In Russian), Sergey N. Gorodsky, Anatoly V. Kurdiukov, Oleg N. Temkin

Sergey N. Gorodsky

No abstract provided.


Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi Sep 2008

Active Species Generation Of Homogeneous Dbd In N2: Experiment And Modelling, N. Gherardi, Et. Es-Sebbar, C. Sarra-Bourret, N. Naudé, F. Massines, D. Tzyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines Jul 2008

Surface Ion-Electron Recombination As The Main Source Of Atoms In Flowing N2 Dbd, D. Tsyganov, Et. Es-Sebbar, S. Pancheshnyi, N. Gherardi, P. Ségur, F. Massines

Dr. Et-touhami Es-sebbar

No abstract provided.


Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau Jul 2008

Talif Quantification Of Nitrogen Atoms Applied To Experimental Simulation Of Titan’S Atmosphere, Et. Es-Sebbar, Y. Benilan, E. Arzoumanian, M.-C. Gazeau

Dr. Et-touhami Es-sebbar

No abstract provided.


S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin Jul 2008

S.E.T.U.P., A New Program Of Representative Simulations Of Titan’S Atmosphere: Current Status, M-C. Gazeau, E. Arzoumanian, Y. Benilan, Et. Es-Sebbar, A. Jolly, S. Perrier, C. Romanzin

Dr. Et-touhami Es-sebbar

No abstract provided.


Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi Jun 2008

Comparison Of Townsend Dielectric Barrier Discharge In N2, N2/O2 And N2/N2o: Behavior And Density Of Radicals, F. Massines, Et. Es-Sebbar, N. Gherardi, N. Naudé, D. Tsyganov, P. Ségur, S. Pancheshnyi

Dr. Et-touhami Es-sebbar

No abstract provided.


Oxidative Carbonylation Of Dimethyl Ethinyl Carbinol In Oscillation Mode (In Russian), Sergey N. Gorodsky, Anatoly V. Kurdiukov Jun 2008

Oxidative Carbonylation Of Dimethyl Ethinyl Carbinol In Oscillation Mode (In Russian), Sergey N. Gorodsky, Anatoly V. Kurdiukov

Sergey N. Gorodsky

No abstract provided.


Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims Feb 2008

Laboratory Experiments As Support To The Built Up Of Titan’S Theoretical Models And Interpretation Of Cassini-Huygens Data, M-C. Gazeau, Y Benilan, Et. Es-Sebbar, T. Ferradaz, E. Hébrard, A. Jolly, F. Raulin, C. Romanzin, J-C. Guillemin, C. Berteloite, A. Canosa, S. D. Le Picard, Ian R. Sims

Dr. Et-touhami Es-sebbar

No abstract provided.


Grain Growth And Texture Development In Lithium Fluoride Thin Films, Hakkwan Kim, Alexander H. King Feb 2008

Grain Growth And Texture Development In Lithium Fluoride Thin Films, Hakkwan Kim, Alexander H. King

Alexander H. King

We have studied grain-growth and texture development in polycrystalline lithium fluoride thin films using dark-field transmission electron microscopy. We demonstrate that we can isolate the size distribution of 〈111〉 surface normal grains from the overall size distribution, based on simple and plausible assumptions about the texture. The {111} texture formation and surface morphology were also observed by x-ray diffraction and atomic force microscopy, respectively. The grain-size distributions become clearly bimodal as the annealing time increases, and we deduce that the short-time size distributions are also a sum of two overlapping peaks. The smaller grain-size peak in the distribution corresponds to …


Stoichiometric Network Analysis And Associated Dimensionless Kinetic Equations. Application To A Model Of The Bray-Liebhafsky Reaction, Zeljko D. Cupic Jan 2008

Stoichiometric Network Analysis And Associated Dimensionless Kinetic Equations. Application To A Model Of The Bray-Liebhafsky Reaction, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


Experimentally Observable Transitions Between Dynamical States In Complex Reaction Systems, Zeljko D. Cupic Jan 2008

Experimentally Observable Transitions Between Dynamical States In Complex Reaction Systems, Zeljko D. Cupic

Zeljko D Cupic

No abstract provided.


Modeling Of Dispersed Phase By Lagrangian Approach In Fluent - 2d Exercise, Kari Myöhänen Jan 2008

Modeling Of Dispersed Phase By Lagrangian Approach In Fluent - 2d Exercise, Kari Myöhänen

Kari Myöhänen

This shows an example calculation applying DPM model in Fluent. This is related to the other DPM presentation and was prepared for the course 'Theory and simulation of dispersed-phase multiphase flows" by Dr. Payman Jalali, Lappeenranta University of Technology.


Modeling Of Dispersed Phase By Lagrangian Approach In Fluent, Kari Myöhänen Jan 2008

Modeling Of Dispersed Phase By Lagrangian Approach In Fluent, Kari Myöhänen

Kari Myöhänen

This is a seminar work prepared for a course 'Theory and simulation of dispersed-phase multiphase flows' by Dr. Payman Jalali, Lappeenranta University of Technology


Near-Monodisperse Ni−Cu Bimetallic Nanocrystals Of Variable Composition: Controlled Synthesis And Catalytic Activity For H2 Generation, Yawen Zhang, Wenyu Huang, Susan E. Habas, John N. Kuhn, Michael E. Grass, Yusuke Yamada, Peidong Yang, Gabor A. Somorjai Jan 2008

Near-Monodisperse Ni−Cu Bimetallic Nanocrystals Of Variable Composition: Controlled Synthesis And Catalytic Activity For H2 Generation, Yawen Zhang, Wenyu Huang, Susan E. Habas, John N. Kuhn, Michael E. Grass, Yusuke Yamada, Peidong Yang, Gabor A. Somorjai

Wenyu Huang

Near-monodisperse Ni1−xCux (x = 0.2−0.8) bimetallic nanocrystals were synthesized by a one-pot thermolysis approach in oleylamine/1-octadecene, using metal acetylacetonates as precursors. The nanocrystals form large-area 2D superlattices, and display a catalytic synergistic effect in the hydrolysis of NaBH4 to generate H2 at x = 0.5 in a strongly basic medium. The Ni0.5Cu0.5 nanocrystals show the lowest activation energy, and also exhibit the highest H2 generation rate at 298 K.


Structure Sensitivity Of Carbon−Nitrogen Ring Opening: Impact Of Platinum Particle Size From Below 1 To 5 Nm Upon Pyrrole Hydrogenation Product Selectivity Over Monodisperse Platinum Nanoparticles Loaded Onto Mesoporous Silica, John N. Kuhn, Wenyu Huang, Chia-Kuang Tsung, Yawen Zhang, Gabor A. Somorjai Jan 2008

Structure Sensitivity Of Carbon−Nitrogen Ring Opening: Impact Of Platinum Particle Size From Below 1 To 5 Nm Upon Pyrrole Hydrogenation Product Selectivity Over Monodisperse Platinum Nanoparticles Loaded Onto Mesoporous Silica, John N. Kuhn, Wenyu Huang, Chia-Kuang Tsung, Yawen Zhang, Gabor A. Somorjai

Wenyu Huang

Well-defined platinum nanoparticles between 0.8 and 5.0 nm were prepared using dendrimer and polymer capping agents and supported onto mesoporous SBA-15 silica. Using these model catalysts, pyrrole hydrogenation was demonstrated to be structure sensitive because ring opening occurred more easily over larger particles compared to smaller ones. The phenomenon is caused by surface roughness or electronic effects that change with particle size.


Dendrimer Templated Synthesis Of One Nanometer Rh And Pt Particles Supported On Mesoporous Silica: Catalytic Activity For Ethylene And Pyrrole Hydrogenation, Wenyu Huang, John N. Kuhn, Chia-Kuang Tsung, Yawen Zhang, Susan E. Habas, Peidong Yang, Gabor A. Somorrjai Jan 2008

Dendrimer Templated Synthesis Of One Nanometer Rh And Pt Particles Supported On Mesoporous Silica: Catalytic Activity For Ethylene And Pyrrole Hydrogenation, Wenyu Huang, John N. Kuhn, Chia-Kuang Tsung, Yawen Zhang, Susan E. Habas, Peidong Yang, Gabor A. Somorrjai

Wenyu Huang

Monodisperse rhodium (Rh) and platinum (Pt) nanoparticles as small as ∼1 nm were synthesized within a fourth generation polyaminoamide (PAMAM) dendrimer, a hyperbranched polymer, in aqueous solution and immobilized by depositing onto a high-surface-area SBA-15 mesoporous support. X-ray photoelectron spectroscopy indicated that the as-synthesized Rh and Pt nanoparticles were mostly oxidized. Catalytic activity of the SBA-15 supported Rh and Pt nanoparticles was studied with ethylene hydrogenation at 273 and 293 K in 10 torr of ethylene and 100 torr of H2 after reduction (76 torr of H2 mixed with 690 torr of He) at different temperatures. Catalysts were active without …


Highly Selective Synthesis Of Catalytically Active Monodisperse Rhodium Nanocubes, Yawen Zhang, Michael E. Grass, John N. Kuhn, Feng Tao, Susan E. Habas, Wenyu Huang, Peidong Yang, Gabor A. Somorjai Jan 2008

Highly Selective Synthesis Of Catalytically Active Monodisperse Rhodium Nanocubes, Yawen Zhang, Michael E. Grass, John N. Kuhn, Feng Tao, Susan E. Habas, Wenyu Huang, Peidong Yang, Gabor A. Somorjai

Wenyu Huang

Monodisperse sub-10 nm Rh nanocubes were synthesized with high selectivity (>85%) by a seedless polyol method. The {100} faces of the Rh NCs were effectively stabilized by chemically adsorbed Br− ions from trimethyl(tetradecyl)ammonium bromide (TTAB). This simple one-step polyol route can be readily applied to the preparation of Pt and Pd nanocubes. Moreover, the organic molecules of PVP and TTAB that encapsulated the Rh nanocubes did not prevent catalytic activity for pyrrole hydrogenation and CO oxidation.


Influence Of Reaction With Xef2 On Surface Adhesion Of Al And Al2o3 Surfaces, Tianfu Zhang, Jeong Park, Wenyu Huang, Gabor A. Somoraji Jan 2008

Influence Of Reaction With Xef2 On Surface Adhesion Of Al And Al2o3 Surfaces, Tianfu Zhang, Jeong Park, Wenyu Huang, Gabor A. Somoraji

Wenyu Huang

The change in surfaceadhesion after fluorination of Al and Al2O3surfaces using XeF2 was investigated with atomic force microscopy. The chemical interaction between XeF2 and Al and Al2O3surfaces was studied by in situx-ray photoelectron spectroscopy. Fresh Al and Al2O3surfaces were obtained by etching top silicon layers of Si∕Al and Si∕Al2O3 with XeF2. The surfaceadhesion and chemical composition were measured after the exposure to air or annealing (at 200°C under vacuum). The correlation between the adhesion force increase and presence of AlF3 on the surface was revealed.


Time-Resolved Investigation Of The Acoustic Vibration Of A Single Gold Nanoprism Pair, J. Burgin, P. Langot, N. Del Fatti, F. Vallee, Wenyu Huang, M.A. El-Sayed Jan 2008

Time-Resolved Investigation Of The Acoustic Vibration Of A Single Gold Nanoprism Pair, J. Burgin, P. Langot, N. Del Fatti, F. Vallee, Wenyu Huang, M.A. El-Sayed

Wenyu Huang

The acoustic vibration of single gold nanoprism pairs on a glass substrate has been investigated in the time-domain combining a spatial modulation spectroscopy microscope with a high-sensitivity femtosecond pump−probe setup. Three modes were observed and ascribed to two in-plane and one out-of-plane vibration of the nanoprisms forming the pair, in agreement with a theoretical analysis. The periods of the two former modes with similar nature show weak (about 10%) and well correlated pair to pair fluctuations that can be unambiguously ascribed to variation of the prism geometry. In contrast, strong fluctuations, by almost a factor of 6, of the mode …


Sub-Two Nanometer Single Crystal Au Nanowires, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Xiaofeng Zhang, Peidong Yang Jan 2008

Sub-Two Nanometer Single Crystal Au Nanowires, Ziyang Huo, Chia-Kuang Tsung, Wenyu Huang, Xiaofeng Zhang, Peidong Yang

Wenyu Huang

Ultrathin single crystal Au nanowires with diameter of ∼1.6 nm and length of few micrometers were synthesized with high yield by simply mixing HAuCl4 and oleylamine at room temperature. High resolution transmission electron microscopy studies revealed that all of these nanowires are single crystalline and grew along the [111] direction. The valency evolution of the gold species during the synthesis was studied by X-ray photoelectron spectroscopy, which showed a clear Au3+ → Au+ → Au stepwise reduction at different reaction stages. Small angle X-ray scattering and small-angle X-ray diffraction suggest mesostructure formation upon HAuCl4 and oleylamine mixing. The slow in …