Thermal Conductivity Reduction Through Isotope Substitution In Nanomaterials: Predictions From An Analytical Classical Model And Nonequilibrium Molecular Dynamics Simulations,
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.
The Occurrence Of False Positive Tests For Gunshot Residue Based On Simulations Of The Suspect's Occupation,
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 and Research 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 all of …
Rayleigh Test Apparatus Design Report,
2011
California Polytechnic State University - San Luis Obispo
Rayleigh Test Apparatus Design Report, Josef Duller, Owen Raybould, James Nicovich
Mechanical Engineering
The Rayleigh Test Apparatus is a device that will be used to test the thermodynamic properties of Nitrous Oxide to assess the feasibility of using this fluid as a coolant for a hybrid rocket aero spike. The aero spike is intended to redirect the propulsion flow as it leaves the engine to create a more efficient flow pattern at low and high altitudes. However, there are issues of overheating which leads to melting of the aero spike. For this reason, the use of nitrous oxide (N2O) as a coolant is being explored. N20 is being considered because it is already …
Comparison Of Horizontal Ground Source (Geothermal) Heat Pump Layouts For Optimal Performance And Thermal Efficiency,
2011
Union College - Schenectady, NY
Comparison Of Horizontal Ground Source (Geothermal) Heat Pump Layouts For Optimal Performance And Thermal Efficiency, Elizabeth M. Bocchino
Honors Theses
This study investigates the difference in thermal efficiencies of horizontal ground source heat pump layouts through computer simulation and experimental modeling. The main objective of this project was to determine if the shape of the layout affects the total heat exchange in a horizontal geothermal system. Geothermal energy is power extracted from the Earth and studies have been focused on increasing the efficiency of the heat transfer from the Earth to the system. Steady state and transient thermal analyses were conducted on two horizontal layout shapes, a U-loop and a coil, in ANSYS Fluent. This system was not full size, …
Transferts De Chaleur Dans Un Réacteur Thermochimique Solaire Muni D’Un Récepteur Volumique Poreux,
2011
Universidad Autónoma Metropolitana Iztapalapa
Transferts De Chaleur Dans Un Réacteur Thermochimique Solaire Muni D’Un Récepteur Volumique Poreux, Hernando Romero Paredes Rubio
Hernando Romero Paredes Rubio
Un réacteur thermochimique solaire de 1 kW muni d’une structure céramique poreuse en céramique est modélisé pour simuler les transferts thermiques a l’intérieur du récepteur volumétrique. Le modèle développé a été utilisé pour prévoir le comportement thermique du réacteur en fonction des différentes conditions opératoires qui concernent le débit de gaz inerte, le flux solaire incident, la porosité, la longueur du récepteur, et la prise en compte de réactions chimiques. Les résultats montrent que la température maximale est de 1850K pour une concentration solaire de 1000 soleils. La température diminue de manière significative lorsque le débit de gaz augmente. Un …
Optimizing Compressed Air Storage For Energy Efficiency,
2011
University of Dayton
Optimizing Compressed Air Storage For Energy Efficiency, Brian Abels, J. Kelly Kissock
Mechanical and Aerospace Engineering Faculty Publications
Compressed air storage is an important, but often misunderstood, component of compressed air systems. This paper discusses methods to properly size compressed air storage in load-unload systems to avoid short cycling and reduce system energy use. First, key equations relating storage, pressure, and compressed air flow are derived using fundamental thermodynamic relations. Next, these relations are used to calculate the relation between volume of storage and cycle time in load-unload compressors. It is shown that cycle time is minimized when compressed air demand is 50% of compressor capacity. The effect of pressure drop between compressor system and storage on cycle …
An Examination Of The Thermodynamics Of Fusion, Vaporization, And Sublimation Of Several Parabens By Correlation Gas Chromatography,
2011
Kasetsart University
An Examination Of The Thermodynamics Of Fusion, Vaporization, And Sublimation Of Several Parabens By Correlation Gas Chromatography, Patamaporn Umnahanant, James Chickos
James Chickos
No abstract provided.
Laser Radiation Co2 Effects In Cement Paste At Different Hydration Stages,
2011
Instituto Tecnológico de Aguascalientes
Laser Radiation Co2 Effects In Cement Paste At Different Hydration Stages, María Del Rosario Moreno-Virgen, Juan Jose Soto-Bernal, Claudio Frausto-Reyes, Adrian Bonilla-Petriciolet, Jose T. Vega-Duran, Jorge Pineda-Piñon, José Angel Ortíz-Lozano
Adrian Bonilla-Petriciolet
In this work the changes occurring in cement pastes irradiated by 10.6µm CO2 laser at diff erent stages of hydration after preparation are presented. Raman spectroscopy, X-ray diffraction and Scanning Electronic Microscopy (SEM) techniques were used to observe molecular structural changes. Intensity of cement paste Raman peaks after laser irradiation was monitored in samples irradiated 2, 3, 4, 5, 6, 7, 8, 9, 10 and 11 days after their preparation. Applied laser power changed Raman peaks intensity at 187.5cm-1, 563cm-1, 695cm-1, 750cm-1, 897cm-1, 1042cm-1 and 1159cm-1 that correspond to compounds already present in cement pastes. X-ray diffraction, SEM images and …
Ant Colony Optimization: A New Stochastic Solver For Modeling Vapor-Liquid Equilibrium Data,
2011
Universidad de Guanajuato
Ant Colony Optimization: A New Stochastic Solver For Modeling Vapor-Liquid Equilibrium Data, Jorge A. Fernández-Vargas, Adrian Bonilla-Petriciolet, Juan Gabriel Segovia-Hernández, Salvador Hernández-Castro
Adrian Bonilla-Petriciolet
In this study, a new stochastic global optimization method based on Ant Colony Optimization (ACO) has been developed and used to solve the parameter estimation problem in vapor-liquid equilibrium data modeling. ACO is a relatively novel stochastic optimization method that mimics foraging behavior of ant colonies. We have developed a new version of ACO, which employs feasible region selection, for performing global optimization in problems with continuous decision variables. The performance of this new ACO has been tested in the modeling of vapor-liquid equilibrium data using both the classical least squares and error-in-variable formulations. Our results show that this new …
Constrained And Unconstrained Gibbs Energy Minimization In Reactive Systems Using Genetic Algorithms And Differential Evolution With Tabu List,
2011
National University of singapore
Constrained And Unconstrained Gibbs Energy Minimization In Reactive Systems Using Genetic Algorithms And Differential Evolution With Tabu List, Adrian Bonilla-Petriciolet, Gade Pandu Rangaiah, Juan Gabriel Segovia-Hernandez
Adrian Bonilla-Petriciolet
Phase equilibrium modeling plays an important role in design, optimization and control of separation processes. The global optimization problem involved in phase equilibrium calculations is very challenging due to the high non-linearity of thermodynamic models especially for multi-component systems subject to chemical reactions. To date, a few attempts have been made in the application of stochastic methods for reactive phase equilibrium calculations compared to those reported for non-reactive systems. In particular, the population-based stochastic methods are known for their good exploration abilities and, when optimal balance between the exploration and exploitation is found, they can be reliable and efficient global …
Evaluation Of Stochastic Global Optimization Methods In The Design Of Complex Distillation Configurations,
2011
Universidad de Guanajuato
Evaluation Of Stochastic Global Optimization Methods In The Design Of Complex Distillation Configurations, Julian Cabrera-Ruiz, Erick Miranda-Galindo, Juan Gabriel Segovia-Hernandez, Salvador Hernandez, Adrian Bonilla-Petriciolet
Adrian Bonilla-Petriciolet
In this chapter, we have implemented several stochastic global optimization methods to obtain the design and optimization of three distillation sequences: multicomponent conventional distillation system, thermally coupled reactive scheme with side stripper, and a dividing wall distillation column. Specifically, these stochastic optimization methods are: Simulated Annealing (SA), Harmony Search (HS) and Genetic Algorithms (GA). Therefore, we have studied the design of these distillation schemes using stochastic global optimization methods coupled to the Aspen One Aspen Plus process simulator for the evaluation of the objective function, ensuring that all results obtained are rigorous. To the best of our knowledge, the evaluation …
A Short Method To Calculate Residue Curve Maps In Multireactive And Multicomponent Systems,
2011
Universidad de Guanajuato
A Short Method To Calculate Residue Curve Maps In Multireactive And Multicomponent Systems, Marcelino Carrera-Rodriguez, Juan Gabriel Segovia-Hernández, Adrian Bonilla-Petriciolet
Adrian Bonilla-Petriciolet
Reactive residue curve maps (RRCM) are useful for the design of reactive distillation columns as a tool to establish feasible zones of reaction-separation. However, the calculation of RRCM usually involves great computational effort due to the nonlinearity of the model equations and its iterative nature for the determination of reactive phase equilibrium. In this study, a simplified method for the generation of RRCM is presented. This method is based on the application of reaction-invariant composition variables and assumes that the phase equilibrium constants (i.e., the relative volatilities) are independent of the temperature. Specifically, the phase equilibrium constants are calculated using …
Phase Equilibrium Modeling In Non-Reactive Systems Using Harmony Search,
2011
Universidad de Guanajuato
Phase Equilibrium Modeling In Non-Reactive Systems Using Harmony Search, Adrian Bonilla-Petriciolet, Didilia I. Mendoza-Castillo, Juan Gabriel Segovia-Hernandez, Juan Carlos Tapia-Picazo
Adrian Bonilla-Petriciolet
This chapter introduces the application of Harmony Search-based algorithms to solve phase stability and equilibrium problems in multicomponent non-reactive systems. Particularly, the performance and capabilities of Harmony Search in the modeling of phase equilibrium is studied and discussed.
Free Radicals Copolymerization Optimization, System: Acrylonitrile-Vinyl Acetate In Cstr,
2011
Instituto Tecnológico de Aguascalientes
Free Radicals Copolymerization Optimization, System: Acrylonitrile-Vinyl Acetate In Cstr, Silvia V. Vallecillo-Gomez, Juan C. Tapia-Picazo, Adrian Bonilla-Petriciolet, Gibran G. De-Alba-Perez-De-Gracia
Adrian Bonilla-Petriciolet
In this work, we study the free radicals solution copolymerization, system acrylonitrile (AN) – vinyl acetate (VA), with the objective to find the parameters of characteristic correlations that are used to determine the reaction autoacceleration phenomenon or gel effect. Two gel effect correlations were evaluated for each monomer. Parameters were found using the stochastic global optimization Simulated Annealing method and experimental data in batch reactor. Gel effect correlations with greater adjustment were used to carry out a sensitivity analysis through continuous stirred tank reactor model. A competence between monomers conversion, average molecular weight of the polymer and the polidispersity was …
Novel Bare-Bones Particle Swarm Optimization And Its Performance For Modeling Vapor-Liquid Equilibrium Data,
2011
National University of singapore
Novel Bare-Bones Particle Swarm Optimization And Its Performance For Modeling Vapor-Liquid Equilibrium Data, Haibo Zhang, Devid D. Kennedy, Gade Pandu Rangaiah, Adrian Bonilla-Petriciolet
Adrian Bonilla-Petriciolet
Parameter estimation in models plays a significant role in developing mathematical models which are used for understanding and analyzing physical, chemical and biological systems. Parameter estimation problems for vapor–liquid equilibrium (VLE) data modeling are very challenging due to the high nonlinearity of thermodynamic models. Recently, stochastic global optimizations and their applications to these problems have attracted greater interest. Of the many stochastic global optimization methods, Bare bones particle swarm optimization (BBPSO) is attractive since it has no parameters to be tuned by the user. In this study, modifications are introduced to the original BBPSO using mutation and crossover operators of …
Batch And Column Studies Of Zn2+ Removal From Aqueous Solution Using Chicken Feathers As Sorbents,
2011
Instituto Tecnológico de Aguascalientes
Batch And Column Studies Of Zn2+ Removal From Aqueous Solution Using Chicken Feathers As Sorbents, Ismael Alejandro Aguayo-Villarreal, Adrian Bonilla-Petriciolet, Virginia Hernández-Montoya, Miguel A. Montes-Morán, Hilda Elizabeth Reynel-Avila
Adrian Bonilla-Petriciolet
We report the removal of zinc ions from aqueous solution by raw chicken feathers using both batch and continuous systems. Specifically, kinetic and sorption isotherms have been determined considering the effect of temperature, pH and metal concentration. Batch sorption data were fitted to various sorption models and results indicate that Zn2+ sorption process using raw chicken feathers followed the pseudo-second order rate model, while sorption isotherms were described properly by Sips isotherm. Sorption isotherms show that the experimental maximum sorption capacity of Zn2+ was found to be 4.31 mg/g at 30 °C and pH 5 and that chemisorption may play …
Role Of The Pericarp Of Carya Illinoinensis As Biosorbent And Precursor Of Activated Carbon For The Removal Of Lead And Acid Blue 25 In Aqueous Solution,
2011
Instituto Tecnológico de Aguascalientes
Role Of The Pericarp Of Carya Illinoinensis As Biosorbent And Precursor Of Activated Carbon For The Removal Of Lead And Acid Blue 25 In Aqueous Solution, Virginia Hernández-Montoya, Didilia I. Mendoza-Castillo, Adrian Bonilla-Petriciolet, María Ana Pérez-Cruz, Miguel A. Montes-Moran
Adrian Bonilla-Petriciolet
The pecan nuts are widely cultivated in states of north of Mexico and the residues generated during nut processing are abundant and not reused. In the present study, the pericarp of pecan (PP) was physicochemically characterized and their use as low cost biosorbent of lead and acid blue 25 was studied in batch systems at different experimental conditions. Also, the PP was used as precursor of activated carbon and a natural modifier agent extracted from egg shells was used in the synthesis of the carbons. Results suggest that the pericarp of pecan (PP) has an acidic character due to the …
Improving The Adsorption Of Heavy Metals From Water Using Commercial Carbons Modified With Egg Shell Wastes,
2011
Instituto Tecnológico de Aguascalientes
Improving The Adsorption Of Heavy Metals From Water Using Commercial Carbons Modified With Egg Shell Wastes, Alejandro Guijarro-Aldaco, Virginia Hernandez-Montoya, Adrian Bonilla-Petriciolet, Miguel A. Montes-Moran, Didilia I. Mendoza-Castillo
Adrian Bonilla-Petriciolet
We introduce the application of hen egg shell waste to improve the adsorption capacities of heavy-metal ions using commercial carbons via the modification of their surface chemistry. Specifically, a calcium solution extracted from egg shell waste has been used as a low-cost activation agent to improve the adsorption properties of three commercial carbons. An orthogonal array of the Taguchi method has been applied to identify the optimal conditions for the adsorbent modification process using the Zn batch adsorption, at 30 °C and pH 5, as the response variable. Our results show that maximum adsorption capacities of Cd, Ni, and Zn …
Kinetic And Thermodynamic Modeling Of Cd+2 And Ni+2 Biosorption By Raw Chicken Feathers,
2011
Universidad de Guanajuato
Kinetic And Thermodynamic Modeling Of Cd+2 And Ni+2 Biosorption By Raw Chicken Feathers, Hilda E. Reynel-Avila, Guadalupe De La Rosa, Cintia Karina Rojas-Mayorga, Irene Cano-Aguilera, Adrian Bonilla-Petriciolet
Adrian Bonilla-Petriciolet
Batch experiments were performed to model kinetic and thermodynamic data for Cd and Ni biosorption by raw chicken feathers (CFs) under different conditions. Results indicated that Cd and Ni sorption onto CFs occurred on the external surface of the biosorbent. Ion removal increased with pH, whereas both endothermic and exothermic stages where observed depending on temperature. Our calculated thermodynamic parameters showed that, below the temperature of 30°C, the metal uptake of Cd and Ni ions may be mainly controlled by a chemisorption process. However, for temperatures higher than 30°C, it is likely that sorption of both metals onto CFs is …
Integrated Differential Evolution For Global Optimization And Its Performance For Modeling Vapor-Liquid Equilibrium Data,
2011
National University of singapore
Integrated Differential Evolution For Global Optimization And Its Performance For Modeling Vapor-Liquid Equilibrium Data, Haibo Zhang, Gade Pandu Rangaiah, Adrian Bonilla-Petriciolet
Adrian Bonilla-Petriciolet
Parameter estimation in thermodynamic models has been of great interest in chemical engineering due to its complex nature such as non-linearity, flat objective function in the neighborhood of global optimum, badly scaled model and non-differential term(s) in the equations. In this paper, a stochastic global optimization algorithm, named, integrated differential evolution (IDE) is introduced to solve the parameter estimation problems for modeling vapor-liquid equilibrium (VLE) data. In IDE, the choice of mutation strategy and associated parameters are adapted according to the learning experience from previous generations. The tabu list used in IDE can avoid revisiting the same area and avoid …
