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Evaluation Of Covariance Matrix Adaptation Evolution Strategy, Shuffled Complex Evolution And Firefly Algorithms For Phase Stability, Phase Equilibrium And Chemical Equilibrium Problems, Seif-Eddeen Fateen, Adrian Bonilla-Petriciolet, Gade Pandu Rangaiah 2012 Cairo University

Evaluation Of Covariance Matrix Adaptation Evolution Strategy, Shuffled Complex Evolution And Firefly Algorithms For Phase Stability, Phase Equilibrium And Chemical Equilibrium Problems, Seif-Eddeen Fateen, Adrian Bonilla-Petriciolet, Gade Pandu Rangaiah

Adrian Bonilla-Petriciolet

Phase equilibrium calculations and phase stability analysis of reactive and non-reactive systems play a significant role in the simulation, design and optimization of reaction and separation processes in chemical engineering. These challenging problems, which are often multivariable and non-convex, require global optimization methods for solving them. Stochastic global optimization algorithms have shown promise in providing reliable and efficient solutions for these thermodynamic problems. In this study, we evaluate three alternative global optimization algorithms for phase and chemical equilibrium calculations, namely, Covariant Matrix Adaptation-Evolution Strategy (CMA-ES), Shuffled Complex Evolution (SCE) and Firefly Algorithm (FA). The performance of these three stochastic algorithms ...


Desarrollo De Microfibras De Carbón De Baja Pureza Y Su Evaluación En La Eliminación De Metales Pesados Del Agua, Juan Carlos Tapia-Picazo, David Vásquez Chávez, Adrian Bonilla-Petriciolet, Antonio Champion Coria, Alberto Alvarez-Castillo, J. Gabriel Luna-Bárcenas 2012 CINVESTAV

Desarrollo De Microfibras De Carbón De Baja Pureza Y Su Evaluación En La Eliminación De Metales Pesados Del Agua, Juan Carlos Tapia-Picazo, David Vásquez Chávez, Adrian Bonilla-Petriciolet, Antonio Champion Coria, Alberto Alvarez-Castillo, J. Gabriel Luna-Bárcenas

Adrian Bonilla-Petriciolet

En este trabajo se presenta el desarrollo de un proceso de fabricación de microfibras de carbón que permite el control de diferentes niveles de pureza y propiedades fisico-químicas de las mismas, para poder utilizarlas en aplicaciones especiales. El proceso de producción incluye las etapas de reacción, hilatura y carbonización. Se reportan los resultados de la evaluación y caracterización de las microfibras de carbón obtenidas en la remoción de metales pesados en agua.


On The Capabilities And Limitations Of Harmony Search For Parameter Estimation In Vapor-Liquid Equilibrium Modeling, Adrian Bonilla-Petriciolet 2012 Instituto Tecnológico de Aguascalientes

On The Capabilities And Limitations Of Harmony Search For Parameter Estimation In Vapor-Liquid Equilibrium Modeling, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

The modeling of vapor-liquid equilibrium data using local composition models is an interesting and challenging global optimization problem in the context of chemical engineering and applied thermodynamics. Until now, several deterministic and stochastic global optimization strategies have been used for modeling vapor-liquid equilibrium (VLE) data. Stochastic optimization methods may offer several advantages for solving global optimization problems and, until now, some meta-heuristics have been tested for modeling phase equilibrium data. However, these optimization strategies usually show a robust performance but, in some challenging problems, they may fail to locate the global optimum. In particular, Harmony Search (HS) is a direct-search ...


Lignocellulosic Precursors Used In The Synthesis Of Activated Carbon: Characterization Techniques And Applications In The Wastewater Treatment, Virginia Hernández-Montoya, Adrian Bonilla-Petriciolet 2012 Instituto Tecnológico de Aguascalientes

Lignocellulosic Precursors Used In The Synthesis Of Activated Carbon: Characterization Techniques And Applications In The Wastewater Treatment, Virginia Hernández-Montoya, Adrian Bonilla-Petriciolet

Adrian Bonilla-Petriciolet

The activated carbon is the universal adsorbent used in the removal of water pollutants such as dyes, heavy metals, fluoride and arsenic, among others. The commercial activated carbons are generally obtained from wood and coconut shell. However, in recent years, other lignocellulosic materials have been used as precursors in the synthesis of this adsorbent for specific applications. This book discusses and analyzes key aspects concerning to the preparation, characterization and application of activated carbons obtained from different lignocellulosic materials. Based on the fact that the activated carbon is used in a broad variety of treatment systems, this book will be ...


Evaluation Of Covariance Matrix Adaptation Evolution Strategy, Shuffled Complex Evolution And Firefly Algorithms For Phase Stability, Phase Equilibrium And Chemical Equilibrium Problems, Seif-Eddeen K. Fateen, Adrián Bonilla-Petriciolet, Gade P. Rangaiah 2012 Cairo University

Evaluation Of Covariance Matrix Adaptation Evolution Strategy, Shuffled Complex Evolution And Firefly Algorithms For Phase Stability, Phase Equilibrium And Chemical Equilibrium Problems, Seif-Eddeen K. Fateen, Adrián Bonilla-Petriciolet, Gade P. Rangaiah

Seif-Eddeen K Fateen

Phase equilibrium calculations and phase stability analysis of reactive and non-reactive systems play a significant role in the simulation, design and optimization of reaction and separation processes in chemical engineering. These challenging problems, which are often multivariable and non-convex, require global optimization methods for solving them. Stochastic global optimization algorithms have shown promise in providing reliable and efficient solutions for these thermodynamic problems. In this study, we evaluate three alternative global optimization algorithms for phase and chemical equilibrium calculations, namely, Covariant Matrix Adaptation - Evolution Strategy (CMA-ES), Shuffled Complex Evolution (SCE) and Firefly Algorithm (FA). The performance of these three stochastic ...


Ogólnotechniczne Podstawy Biotechnologii Z Elementami Grafiki Inżynierskiej Ćw., Wojciech M. Budzianowski 2012 Wroclaw University of Technology

Ogólnotechniczne Podstawy Biotechnologii Z Elementami Grafiki Inżynierskiej Ćw., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Materiały Odstresowujące, Wojciech M. Budzianowski 2012 Wroclaw University of Technology

Materiały Odstresowujące, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Lanthanide Coordination Polymers With Tetrafluoroterephthalate As A Bridging Ligand: Thermal And Optical Properties, Christiane Seidel, Chantal Lorbeer, Joanna Cyninska, Anja V. Mudring, Uwe Ruschewitz 2012 University of Cologne

Lanthanide Coordination Polymers With Tetrafluoroterephthalate As A Bridging Ligand: Thermal And Optical Properties, Christiane Seidel, Chantal Lorbeer, Joanna Cyninska, Anja V. Mudring, Uwe Ruschewitz

Anja V. Mudring

Seven new coordination polymers ∞2[Ln(tfBDC)(NO3)(DMF)2]·DMF (Ln3+ = Ce, Pr, Nd, Sm, Dy, Er, Yb) with the perfluorinated linker ligand tetrafluoroterephthalate (tfBDC2−) have been synthesized. Their crystal structures consist of layers (44 nets) weakly bound by van der Waals interactions. In addition, differential thermal analysis/thermogravimetry (DTA/TG) curves, as well as absorption and emission spectra, have been recorded for all compounds.


Melting Point Suppression In New Lanthanoid(Iii) Ionic Liquids By Trapping Of Kinetic Polymorphs: An In Situsynchrotron Powder Diffraction Study, Anthony S.R. Chesman, Mei Yang, Bert Mallick, Tamsyn M. Ross, Ian A. Gass, Glen B. Deacon, Stuart R. Batten, Anja V. Mudring 2012 Monash University

Melting Point Suppression In New Lanthanoid(Iii) Ionic Liquids By Trapping Of Kinetic Polymorphs: An In Situsynchrotron Powder Diffraction Study, Anthony S.R. Chesman, Mei Yang, Bert Mallick, Tamsyn M. Ross, Ian A. Gass, Glen B. Deacon, Stuart R. Batten, Anja V. Mudring

Anja V. Mudring

he inclusion of lanthanoids in ionic liquids (ILs) offers an ideal route to incorporate their unique luminescent and magnetic properties into a bulk solution.1,2 However, lanthanoid compounds often exhibit a poor solubility in commonly used ILs because the IL anions are typically very weakly coordinating, prohibiting the simple dissolution of a lanthanoid salt by complexation to any beneficial extent.2 One strategy used to achieve high lanthanoid concentrations is to incorporate the lanthanoid cation directly into an anion that will form ILs.3 This is best accomplished by employing a ligand which readily coordinates to a lanthanoid atom ...


High Speed Flow Simulation In Fuel Injector Nozzles, Sukanta Rakshit 2012 University of Massachusetts Amherst

High Speed Flow Simulation In Fuel Injector Nozzles, Sukanta Rakshit

Masters Theses 1911 - February 2014

Atomization of fuel is essential in controlling combustion inside a direct injection engine. Controlling combustion helps in reducing emissions and boosting efficiency. Cavitation is one of the factors that significantly affect the nature of spray in a combustion chamber. Typical fuel injector nozzles are small and operate at a very high pressure, which limit the study of internal nozzle behavior. The time and length scales further limit the experimental study of a fuel injector nozzle. Simulating cavitation in a fuel injector will help in understanding the phenomenon and will assist in further development.

The construction of any simulation of cavitating ...


Heat Transfer Enhancement In A Straight Channel Via A Rotationally Oscillating Adiabatic Cylinder, Ali Beskok, Mehrdad Raisee, Bayram Celik, Bedri Yagiz, Mohsen Cheraghi 2012 Old Dominion University

Heat Transfer Enhancement In A Straight Channel Via A Rotationally Oscillating Adiabatic Cylinder, Ali Beskok, Mehrdad Raisee, Bayram Celik, Bedri Yagiz, Mohsen Cheraghi

Mechanical & Aerospace Engineering Faculty Publications

Heat convection from the uniformly heated walls of a straight channel in presence of a rotationally oscillating cylinder (ROC) is simulated at Re = 100. Heat transfer enhancement due to vortex shedding from the ROC is investigated. Systematic studies are performed to explore the rotation angle and frequency influences on heat transfer by varying the latter in range of the lock-in regime and the former from 0 to 2 π/3. All simulation results are based on the numerical solutions of two-dimensional, unsteady, incompressible Navier-Stokes and energy equations using an h/p type finite element algorithm. Considering time periodicity of the ...


Structure Evolution And Dielectric Behavior Of Polystyrene-Capped Barium Titanate Nanoparticles, H.Z. Guo, Yaroslav Mudryk, M.I. Ahmad, X.C. Pang, L. Zhao, M. Akinc, Vitalij K. Pecharsky, Nicola Bowler, Z.Q. Lin, Xiaoli Tan 2012 Iowa State University

Structure Evolution And Dielectric Behavior Of Polystyrene-Capped Barium Titanate Nanoparticles, H.Z. Guo, Yaroslav Mudryk, M.I. Ahmad, X.C. Pang, L. Zhao, M. Akinc, Vitalij K. Pecharsky, Nicola Bowler, Z.Q. Lin, Xiaoli Tan

Materials Science and Engineering Publications

Polystyrene-capped barium titanate (BaTiO3) nanoparticles with sizes of 11 nm and 27 nm were prepared using amphiphilic star-like diblock copolymer templates. The crystal structure evolution of these nanoparticles over a wide temperature range (10-428 K) was investigated by powder X-ray diffraction. The Rietveld refinement indicates that the abrupt structural transitions observed in micron-sized powders become broad as particle size is reduced to a few tens of nanometers. The orthorhombic phase (Amm2) is observed in the range of 10-388 K, coexisting with the rhombohedral phase (R3c) at lower temperatures and with the tetragonal phase (P4mm) at higher temperatures. At room temperature ...


Hydrogen Production From Biogas By Oxy-Reforming: Reaction System Analysis, Aleksandra Terlecka, Wojciech M. Budzianowski 2011 Wroclaw University of Technology

Hydrogen Production From Biogas By Oxy-Reforming: Reaction System Analysis, Aleksandra Terlecka, Wojciech M. Budzianowski

Wojciech Budzianowski

Oxy-reforming is emerging as an interesting alternative to conventional methods of hydrogen generation. The current article characterises this process through analysis of individual reactions: SMR (steam methane reforming), WGS (water gas shift) and CPO (catalytic partial oxidation). Analyses relate to optimisation of thermal conditions thus enabling cost-effectivenes of the process.


Analysis Of Biomass/Coal Co-Gasification For Integrated Gasification Combined Cycle (Igcc) Systems With Carbon Capture, Henry A. Long III 2011 University of New Orleans

Analysis Of Biomass/Coal Co-Gasification For Integrated Gasification Combined Cycle (Igcc) Systems With Carbon Capture, Henry A. Long Iii

University of New Orleans Theses and Dissertations

In recent years, Integrated Gasification Combined Cycle Technology (IGCC) has become more common in clean coal power operations with carbon capture and sequestration (CCS). Great efforts have been spent on investigating ways to improve the efficiency, reduce costs, and further reduce greenhouse gas emissions. This study focuses on investigating two approaches to achieve these goals. First, replace the subcritical Rankine steam cycle with a supercritical steam cycle. Second, add different amounts of biomass as feedstock to reduce emissions. Finally, implement several types of CCS, including sweet- and sour-shift pre-combustion and post-combustion.

Using the software, Thermoflow®, this study shows that utilizing ...


Lectio Praecursoria, Kari Myöhänen 2011 Lappeenranta University of Technology

Lectio Praecursoria, Kari Myöhänen

Kari Myöhänen

Lectio praecursoria: Modelling of combustion and sorbent reactions in three-dimensional flow environment of a circulating fluidized bed furnace


A Coarse-Grained Model For Polyethylene Glycol (Peg) Polymer, Qifei Wang, David Keffer, Donald Nicholson 2011 University of Tennessee - Knoxville

A Coarse-Grained Model For Polyethylene Glycol (Peg) Polymer, Qifei Wang, David Keffer, Donald Nicholson

David Keffer

A coarse-grained (CG) model of polyethylene glycol (PEG) was developed and implemented in CG molecular dynamics (MD) simulations of PEG chains with degree of polymerization (DP) 20 and 40. In the model, two repeat units of PEG are grouped as one CG bead. Atomistic MD simulation of PEG chains with DP = 20 was first conducted to obtain the bonded structural probability distribution functions (PDFs) and nonbonded pair correlation function (PCF) of the CG beads. The bonded CG potentials are obtained by simple inversion of the corresponding PDFs. The CG nonbonded potential is parameterized to the PCF using both an inversion ...


Reactive Molecular Dynamics Study Of Proton Transport In Polymer Electrolyte Membranes, Myvizhi Esai Selvan, David Keffer, Shengting Cui 2011 University of Tennessee - Knoxville

Reactive Molecular Dynamics Study Of Proton Transport In Polymer Electrolyte Membranes, Myvizhi Esai Selvan, David Keffer, Shengting Cui

David Keffer

Dynamical properties of water and protons in Nafion with an equivalent weight of 1144 are studied using the recently developed reactive molecular dynamics (RMD) algorithm at various water contents. The structural diffusion of a proton along the aqueous domains is modeled via a mechanism similar to that observed in bulk aqueous systems. The algorithm implements reactivity in classical MD simulations by three steps: (i) satisfaction of the trigger, (ii) instantaneous reaction, and (iii) local equilibration. Two different schemes (Method 1 and Method 2) of execution of the algorithm are investigated, which differ in terms of the range of the local ...


Thermal Conductivity Reduction Through Isotope Substitution In Nanomaterials: Predictions From An Analytical Classical Model And Nonequilibrium Molecular Dynamics Simulations, Ganesh Balasubramanian, Ishwar K. Puri, Michael C. Bohm, Frederic Leroy 2011 Virginia Polytechnic Institute and State University

Thermal Conductivity Reduction Through Isotope Substitution In Nanomaterials: Predictions From An Analytical Classical Model And Nonequilibrium Molecular Dynamics Simulations, Ganesh Balasubramanian, Ishwar K. Puri, Michael C. Bohm, Frederic Leroy

Ganesh Balasubramanian

We introduce an analytical model to rapidly determine the thermal conductivity reduction due to mass disorder in nanomaterials. Although this simplified classical model depends only on the masses of the different atoms, it adequately describes the changes in thermal transport as the concentrations of these atoms vary. Its predictions compare satisfactorily with nonequilibrium molecular dynamics simulations of the thermal conductivity of 14C–12C carbon nanotubes as well as with previous simulations of other materials. We present it as a simple tool to quantitatively estimate the thermal conductivity decrease that is induced by isotope substitution in various materials.


A Review Of X-Ray Flow Visualization With Applications To Multiphase Flows, Theodore J. Heindel 2011 Iowa State University

A Review Of X-Ray Flow Visualization With Applications To Multiphase Flows, Theodore J. Heindel

Mechanical Engineering Publications

Flow visualization and characterization of multiphase flows have been the quest of many fluid mechanicians. The process is fairly straight forward only when there is good optical access (i.e., the vessel is not opaque or there are appropriate viewing ports) and the flow is transparent, implying a very low volume fraction of the dispersed phase; however, when optical access is not good or the fluid is opaque, alternative methods must be developed. Several different noninvasive visualization tools have been developed to provide high-quality qualitative and quantitative data of various multiphase flow characteristics, and overviews of these methods have appeared ...


The Occurrence Of False Positive Tests For Gunshot Residue Based On Simulations Of The Suspect's Occupation, Christopher R. Dockery, Matthew B. Rosenberg, Kimberly Kammerdiener, Lauren E. McAdams 2011 Kennesaw State University

The Occurrence Of False Positive Tests For Gunshot Residue Based On Simulations Of The Suspect's Occupation, Christopher R. Dockery, Matthew B. Rosenberg, Kimberly Kammerdiener, Lauren E. Mcadams

Faculty Publications

Samples collected from high-risk occupations, or simulations thereof, are analyzed for elemental composition using laser-induced breakdown spectroscopy (LlBS) to determine the occurrence of false positive gunshot residue results generated in the work environment. Previous work involving the study of lifetime of detectable amounts of gunshot residue on the hands of a suspect shooter found that gunshot residue exists up to 5.27 days after a firearm discharge. However, certain environmental and/or occupational false positive tests for gunshot residue could result when sampling non-shooters. Samples collected from occupations or simulations thereof include welding, pyrotechnics, key cutting, mechanics, and paper products ...


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